3 .\" Copyright 2003 Ximian, Inc.
4 .\" Copyright 2004-2011 Novell, Inc.
5 .\" Copyright 2011-2012 Xamarin Inc
6 .\" Copyright 2013 7digital Media Ltd.
8 .\" Miguel de Icaza (miguel@gnu.org)
12 mono \- Mono's ECMA-CLI native code generator (Just-in-Time and Ahead-of-Time)
15 .B mono [options] file [arguments...]
17 .B mono-sgen [options] file [arguments...]
19 \fImono\fP is a runtime implementation of the ECMA Common Language
20 Infrastructure. This can be used to run ECMA and .NET applications.
22 The runtime contains a native code generator that transforms the
23 Common Intermediate Language into native code.
25 The code generator can operate in two modes: just in time compilation
26 (JIT) or ahead of time compilation (AOT). Since code can be
27 dynamically loaded, the runtime environment and the JIT are always
28 present, even if code is compiled ahead of time.
30 The runtime loads the specified
37 is an ECMA assembly. They typically have a .exe or .dll extension.
39 The runtime provides a number of configuration options for running
40 applications, for developing and debugging, and for testing and
41 debugging the runtime itself.
43 The \fImono\fP command uses the Boehm conservative garbage collector
44 while the \fImono-sgen\fP command uses a moving and generational
47 On Unix-based systems, Mono provides a mechanism to emulate the
48 Windows-style file access, this includes providing a case insensitive
49 view of the file system, directory separator mapping (from \\ to /) and
50 stripping the drive letters.
52 This functionality is enabled by setting the
54 environment variable to one of
59 See the description for
61 in the environment variables section for more details.
63 The following options are available:
65 \fB--aot\fR, \fB--aot[=options]\fR
66 This option is used to precompile the CIL code in the specified
67 assembly to native code. The generated code is stored in a file with
68 the extension .so. This file will be automatically picked up by the
69 runtime when the assembly is executed.
71 Ahead-of-Time compilation is most useful if you use it in combination
72 with the -O=all,-shared flag which enables all of the optimizations in
73 the code generator to be performed. Some of those optimizations are
74 not practical for Just-in-Time compilation since they might be very
77 Unlike the .NET Framework, Ahead-of-Time compilation will not generate
78 domain independent code: it generates the same code that the
79 Just-in-Time compiler would produce. Since most applications use a
80 single domain, this is fine. If you want to optimize the generated
81 code for use in multi-domain applications, consider using the
84 This pre-compiles the methods, but the original assembly is still
85 required to execute as this one contains the metadata and exception
86 information which is not available on the generated file. When
87 precompiling code, you might want to compile with all optimizations
88 (-O=all). Pre-compiled code is position independent code.
90 Pre compilation is just a mechanism to reduce startup time, increase
91 code sharing across multiple mono processes and avoid just-in-time
92 compilation program startup costs. The original assembly must still
93 be present, as the metadata is contained there.
95 AOT code typically can not be moved from one computer to another
96 (CPU-specific optimizations that are detected at runtime) so you
97 should not try to move the pre-generated assemblies or package the
98 pre-generated assemblies for deployment.
100 A few options are available as a parameter to the
102 command line option. The options are separated by commas, and more
103 than one can be specified:
108 The AOT compiler will emit a (ELF only) library initializer to automatically
109 register the aot compiled module with the runtime. This is only useful in static
113 Instructs the AOT compiler to output assembly code instead of an
116 .I bind-to-runtime-version
118 If specified, forces the generated AOT files to be bound to the
119 runtime version of the compiling Mono. This will prevent the AOT
120 files from being consumed by a different Mono runtime.
123 This is currently an experimental feature as it is not complete.
124 This instructs Mono to precompile code that has historically not been
125 precompiled with AOT.
129 When this option is specified, P/Invoke methods are invoked directly
130 instead of going through the operating system symbol lookup operation.
132 .I llvm-path=<PREFIX>
133 Same for the llvm tools 'opt' and 'llc'.
136 Use the GNU style target triple <TRIPLE> to determine some code generation options, i.e.
137 --mtriple=armv7-linux-gnueabi will generate code that targets ARMv7. This is currently
138 only supported by the ARM backend. In LLVM mode, this triple is passed on to the LLVM
141 .I nimt-trampolines=[number]
142 When compiling in full aot mode, the IMT trampolines must be precreated
143 in the AOT image. You can add additional method trampolines with this argument.
147 Instructs the AOT compiler to not output any debugging information.
150 Instructs the AOT compiler to emit DWARF debugging information. When
151 used together with the nodebug option, only DWARF debugging
152 information is emitted, but not the information that can be used at
155 .I nrgctx-trampolines=[number]
156 When compiling in full aot mode, the generic sharing trampolines must be precreated
157 in the AOT image. You can add additional method trampolines with this argument.
160 .I ntrampolines=[number]
161 When compiling in full aot mode, the method trampolines must be precreated
162 in the AOT image. You can add additional method trampolines with this argument.
165 .I outfile=[filename]
166 Instructs the AOT compiler to save the output to the specified file.
168 .I print-skipped-methods
169 If the AOT compiler cannot compile a method for any reason, enabling this flag
170 will output the skipped methods to the console.
172 .I readonly-value=namespace.typename.fieldname=type/value
173 Override the value of a static readonly field. Usually, during JIT
174 compilation, the static constructor is ran eagerly, so the value of
175 a static readonly field is known at compilation time and the compiler
176 can do a number of optimizations based on it. During AOT, instead, the static
177 constructor can't be ran, so this option can be used to set the value of such
178 a field and enable the same set of optimizations.
179 Type can be any of i1, i2, i4 for integers of the respective sizes (in bytes).
180 Note that signed/unsigned numbers do not matter here, just the storage size.
181 This option can be specified multiple times and it doesn't prevent the static
182 constructor for the type defining the field to execute with the usual rules
183 at runtime (hence possibly computing a different value for the field).
186 .I save-temps,keep-temps
187 Instructs the AOT compiler to keep temporary files.
190 This instructs the compiler to generate sequence point checks that
191 allow Mono's soft debugger to debug applications even on systems where
192 it is not possible to set breakpoints or to single step (certain
193 hardware configurations like the cell phones and video gaming
197 Create an ELF object file (.o) or .s file which can be statically linked into an
198 executable when embedding the mono runtime. When this option is used, the object file
199 needs to be registered with the embedded runtime using the mono_aot_register_module
200 function which takes as its argument the mono_aot_module_<ASSEMBLY NAME>_info global
201 symbol from the object file:
204 extern void *mono_aot_module_hello_info;
206 mono_aot_register_module (mono_aot_module_hello_info);
211 Print various stats collected during AOT compilation.
214 This is an experimental option for the AOT compiler to use multiple threads
215 when compiling the methods.
217 .I tool-prefix=<PREFIX>
218 Prepends <PREFIX> to the name of tools ran by the AOT compiler, i.e. 'as'/'ld'. For
219 example, --tool=prefix=arm-linux-gnueabi- will make the AOT compiler run
220 'arm-linux-gnueabi-as' instead of 'as'.
223 Instructs the AOT compiler to emit debug symbol information.
225 For more information about AOT, see: http://www.mono-project.com/docs/advanced/aot/
228 \fB--attach=[options]\fR
229 Currently the only option supported by this command line argument is
230 \fBdisable\fR which disables the attach functionality.
232 \fB--config filename\fR
233 Load the specified configuration file instead of the default one(s).
234 The default files are /etc/mono/config and ~/.mono/config or the file
235 specified in the MONO_CONFIG environment variable, if set. See the
236 mono-config(5) man page for details on the format of this file.
238 \fB--debugger-agent=[options]\fR
239 This instructs the Mono runtime to
240 start a debugging agent inside the Mono runtime and connect it to a
241 client user interface will control the Mono process.
242 This option is typically used by IDEs, like the MonoDevelop IDE.
244 The configuration is specified using one of more of the following options:
250 Use this option to specify the IP address where your debugger client is
255 Specifies the diagnostics log level for
259 Used to specify the file where the log will be stored, it defaults to
263 Defaults to no, with the default option Mono will actively connect to the
264 host/port configured with the \fBaddress\fR option. If you set it to 'y', it
265 instructs the Mono runtime to start debugging in server mode, where Mono
266 actively waits for the debugger front end to connect to the Mono process.
267 Mono will print out to stdout the IP address and port where it is listening.
270 If set to yes, Mono will call \fBsetpgid(0, 0)\fB on startup, if that function
271 is available on the system. This is useful for ensuring that signals delivered
272 to a process that is executing the debuggee are not propagated to the debuggee,
273 e.g. when Ctrl-C sends \fBSIGINT\fB to the \fBsdb\fB tool.
276 Defaults to yes, with the default option Mono will suspend the vm on startup
277 until it connects successfully to a debugger front end. If you set it to 'n', in
278 conjunction with \fBserver=y\fR, it instructs the Mono runtime to run as normal,
279 while caching metadata to send to the debugger front end on connection..
281 .I transport=transport_name
283 This is used to specify the transport that the debugger will use to
284 communicate. It must be specified and currently requires this to
290 Configures the virtual machine to be better suited for desktop
291 applications. Currently this sets the GC system to avoid expanding
292 the heap as much as possible at the expense of slowing down garbage
296 This is an experimental flag that instructs the Mono runtime to not
297 generate any code at runtime and depend exclusively on the code
298 generated from using mono --aot=full previously. This is useful for
299 platforms that do not permit dynamic code generation.
301 Notice that this feature will abort execution at runtime if a codepath
302 in your program, or Mono's class libraries attempts to generate code
303 dynamically. You should test your software upfront and make sure that
304 you do not use any dynamic features.
306 \fB--gc=boehm\fR, \fB--gc=sgen\fR
307 Selects the Garbage Collector engine for Mono to use, Boehm or SGen.
308 Currently this merely ensures that you are running either the
309 \fImono\fR or \fImono-sgen\fR commands. This flag can be set in the
310 \fBMONO_ENV_OPTIONS\fR environment variable to force all of your child
311 processes to use one particular kind of GC with the Mono runtime.
313 \fB--help\fR, \fB-h\fR
314 Displays usage instructions.
317 If the Mono runtime has been compiled with LLVM support (not available
318 in all configurations), Mono will use the LLVM optimization and code
319 generation engine to JIT or AOT compile.
321 For more information, consult: http://www.mono-project.com/docs/advanced/mono-llvm/
324 When using a Mono that has been compiled with LLVM support, it forces
325 Mono to fallback to its JIT engine and not use the LLVM backend.
327 \fB--optimize=MODE\fR, \fB-O=MODE\fR
328 MODE is a comma separated list of optimizations. They also allow
329 optimizations to be turned off by prefixing the optimization name with
332 In general, Mono has been tuned to use the default set of flags,
333 before using these flags for a deployment setting, you might want to
334 actually measure the benefits of using them.
336 The following optimizations are implemented:
338 all Turn on all optimizations
339 peephole Peephole postpass
340 branch Branch optimizations
341 inline Inline method calls
342 cfold Constant folding
343 consprop Constant propagation
344 copyprop Copy propagation
345 deadce Dead code elimination
346 linears Linear scan global reg allocation
347 cmov Conditional moves [arch-dependency]
348 shared Emit per-domain code
349 sched Instruction scheduling
350 intrins Intrinsic method implementations
351 tailc Tail recursion and tail calls
352 loop Loop related optimizations
353 fcmov Fast x86 FP compares [arch-dependency]
354 leaf Leaf procedures optimizations
355 aot Usage of Ahead Of Time compiled code
356 precomp Precompile all methods before executing Main
357 abcrem Array bound checks removal
358 ssapre SSA based Partial Redundancy Elimination
359 sse2 SSE2 instructions on x86 [arch-dependency]
360 gshared Enable generic code sharing.
363 For example, to enable all the optimization but dead code
364 elimination and inlining, you can use:
366 -O=all,-deadce,-inline
369 The flags that are flagged with [arch-dependency] indicate that the
370 given option if used in combination with Ahead of Time compilation
371 (--aot flag) would produce pre-compiled code that will depend on the
372 current CPU and might not be safely moved to another computer.
374 \fB--runtime=VERSION\fR
375 Mono supports different runtime versions. The version used depends on the program
376 that is being run or on its configuration file (named program.exe.config). This option
377 can be used to override such autodetection, by forcing a different runtime version
378 to be used. Note that this should only be used to select a later compatible runtime
379 version than the one the program was compiled against. A typical usage is for
380 running a 1.1 program on a 2.0 version:
382 mono --runtime=v2.0.50727 program.exe
385 \fB--security\fR, \fB--security=mode\fR
386 Activate the security manager, a currently experimental feature in
387 Mono and it is OFF by default. The new code verifier can be enabled
388 with this option as well.
392 Using security without parameters is equivalent as calling it with the
395 The following modes are supported:
398 This allows mono to support declarative security attributes,
399 e.g. execution of Code Access Security (CAS) or non-CAS demands.
402 Enables the core-clr security system, typically used for
403 Moonlight/Silverlight applications. It provides a much simpler
404 security system than CAS, see http://www.mono-project.com/docs/web/moonlight/
405 for more details and links to the descriptions of this new system.
408 Enables the new verifier and performs basic verification for code
409 validity. In this mode, unsafe code and P/Invoke are allowed. This
410 mode provides a better safety guarantee but it is still possible
411 for managed code to crash Mono.
414 Enables the new verifier and performs full verification of the code
415 being executed. It only allows verifiable code to be executed.
416 Unsafe code is not allowed but P/Invoke is. This mode should
417 not allow managed code to crash mono. The verification is not as
418 strict as ECMA 335 standard in order to stay compatible with the MS
421 The security system acts on user code: code contained in mscorlib or
422 the global assembly cache is always trusted.
427 Configures the virtual machine to be better suited for server
428 operations (currently, allows a heavier threadpool initialization).
431 Verifies mscorlib and assemblies in the global
432 assembly cache for valid IL, and all user code for IL
435 This is different from \fB--security\fR's verifiable
436 or validil in that these options only check user code and skip
437 mscorlib and assemblies located on the global assembly cache.
439 \fB-V\fR, \fB--version\fR
440 Prints JIT version information (system configuration, release number
441 and branch names if available).
444 .SH DEVELOPMENT OPTIONS
445 The following options are used to help when developing a JITed application.
447 \fB--debug\fR, \fB--debug=OPTIONS\fR
448 Turns on the debugging mode in the runtime. If an assembly was
449 compiled with debugging information, it will produce line number
450 information for stack traces.
454 The optional OPTIONS argument is a comma separated list of debugging
455 options. These options are turned off by default since they generate
456 much larger and slower code at runtime.
458 The following options are supported:
461 Produces a detailed error when throwing a InvalidCastException. This
462 option needs to be enabled as this generates more verbose code at
466 Disable some JIT optimizations which are usually only disabled when
467 running inside the debugger. This can be helpful if you want to attach
468 to the running process with mdb.
471 Generate and register debugging information with gdb. This is only supported on some
472 platforms, and only when using gdb 7.0 or later.
476 \fB--profile[=profiler[:profiler_args]]\fR
477 Turns on profiling. For more information about profiling applications
478 and code coverage see the sections "PROFILING" and "CODE COVERAGE"
481 This option can be used multiple times, each time will load an
482 additional profiler. This allows developers to use modules that
483 extend the JIT through the Mono profiling interface.
485 \fB--trace[=expression]\fR
486 Shows method names as they are invoked. By default all methods are
489 The trace can be customized to include or exclude methods, classes or
490 assemblies. A trace expression is a comma separated list of targets,
491 each target can be prefixed with a minus sign to turn off a particular
492 target. The words `program', `all' and `disabled' have special
493 meaning. `program' refers to the main program being executed, and
494 `all' means all the method calls.
496 The `disabled' option is used to start up with tracing disabled. It
497 can be enabled at a later point in time in the program by sending the
498 SIGUSR2 signal to the runtime.
500 Assemblies are specified by their name, for example, to trace all
501 calls in the System assembly, use:
504 mono --trace=System app.exe
507 Classes are specified with the T: prefix. For example, to trace all
508 calls to the System.String class, use:
511 mono --trace=T:System.String app.exe
514 And individual methods are referenced with the M: prefix, and the
515 standard method notation:
518 mono --trace=M:System.Console:WriteLine app.exe
521 Exceptions can also be traced, it will cause a stack trace to be
522 printed every time an exception of the specified type is thrown.
523 The exception type can be specified with or without the namespace,
524 and to trace all exceptions, specify 'all' as the type name.
527 mono --trace=E:System.Exception app.exe
530 As previously noted, various rules can be specified at once:
533 mono --trace=T:System.String,T:System.Random app.exe
536 You can exclude pieces, the next example traces calls to
537 System.String except for the System.String:Concat method.
540 mono --trace=T:System.String,-M:System.String:Concat
543 You can trace managed to unmanaged transitions using
544 the wrapper qualifier:
547 mono --trace=wrapper app.exe
550 Finally, namespaces can be specified using the N: prefix:
553 mono --trace=N:System.Xml
557 \fB--no-x86-stack-align\fR
558 Don't align stack frames on the x86 architecture. By default, Mono
559 aligns stack frames to 16 bytes on x86, so that local floating point
560 and SIMD variables can be properly aligned. This option turns off the
561 alignment, which usually saves one intruction per call, but might
562 result in significantly lower floating point and SIMD performance.
565 Generate a JIT method map in a /tmp/perf-PID.map file. This file is then
566 used, for example, by the perf tool included in recent Linux kernels.
567 Each line in the file has:
570 HEXADDR HEXSIZE methodname
573 Currently this option is only supported on Linux.
574 .SH JIT MAINTAINER OPTIONS
575 The maintainer options are only used by those developing the runtime
576 itself, and not typically of interest to runtime users or developers.
579 Inserts a breakpoint before the method whose name is `method'
580 (namespace.class:methodname). Use `Main' as method name to insert a
581 breakpoint on the application's main method. You can use it also with
582 generics, for example "System.Collections.Generic.Queue`1:Peek"
585 Inserts a breakpoint on exceptions. This allows you to debug your
586 application with a native debugger when an exception is thrown.
589 This compiles a method (namespace.name:methodname), this is used for
590 testing the compiler performance or to examine the output of the code
594 Compiles all the methods in an assembly. This is used to test the
595 compiler performance or to examine the output of the code generator
597 \fB--graph=TYPE METHOD\fR
598 This generates a postscript file with a graph with the details about
599 the specified method (namespace.name:methodname). This requires `dot'
600 and ghostview to be installed (it expects Ghostview to be called
603 The following graphs are available:
605 cfg Control Flow Graph (CFG)
607 code CFG showing code
608 ssa CFG showing code after SSA translation
609 optcode CFG showing code after IR optimizations
612 Some graphs will only be available if certain optimizations are turned
616 Instruct the runtime on the number of times that the method specified
617 by --compile (or all the methods if --compileall is used) to be
618 compiled. This is used for testing the code generator performance.
621 Displays information about the work done by the runtime during the
622 execution of an application.
624 \fB--wapi=hps|semdel\fR
625 Perform maintenance of the process shared data.
627 semdel will delete the global semaphore.
629 hps will list the currently used handles.
631 \fB-v\fR, \fB--verbose\fR
632 Increases the verbosity level, each time it is listed, increases the
633 verbosity level to include more information (including, for example,
634 a disassembly of the native code produced, code selector info etc.).
636 The Mono runtime allows external processes to attach to a running
637 process and load assemblies into the running program. To attach to
638 the process, a special protocol is implemented in the Mono.Management
641 With this support it is possible to load assemblies that have an entry
642 point (they are created with -target:exe or -target:winexe) to be
643 loaded and executed in the Mono process.
645 The code is loaded into the root domain, and it starts execution on
646 the special runtime attach thread. The attached program should
647 create its own threads and return after invocation.
649 This support allows for example debugging applications by having the
650 csharp shell attach to running processes.
652 The mono runtime includes a profiler that can be used to explore
653 various performance related problems in your application. The
654 profiler is activated by passing the --profile command line argument
655 to the Mono runtime, the format is:
658 --profile[=profiler[:profiler_args]]
661 Mono has a built-in profiler called 'default' (and is also the default
662 if no arguments are specified), but developers can write custom
663 profilers, see the section "CUSTOM PROFILERS" for more details.
667 is not specified, the default profiler is used.
671 is a profiler-specific string of options for the profiler itself.
673 The default profiler accepts the following options 'alloc' to profile
674 memory consumption by the application; 'time' to profile the time
675 spent on each routine; 'jit' to collect time spent JIT-compiling methods
676 and 'stat' to perform sample statistical profiling.
677 If no options are provided the default is 'alloc,time,jit'.
680 profile data is printed to stdout: to change this, use the 'file=filename'
681 option to output the data to filename.
686 mono --profile program.exe
690 That will run the program with the default profiler and will do time
691 and allocation profiling.
695 mono --profile=default:stat,alloc,file=prof.out program.exe
698 Will do sample statistical profiling and allocation profiling on
699 program.exe. The profile data is put in prof.out.
701 Note that the statistical profiler has a very low overhead and should
702 be the preferred profiler to use (for better output use the full path
703 to the mono binary when running and make sure you have installed the
704 addr2line utility that comes from the binutils package).
706 This is the most advanced profiler.
708 The Mono \f[I]log\f[] profiler can be used to collect a lot of
709 information about a program running in the Mono runtime.
710 This data can be used (both while the process is running and later)
711 to do analyses of the program behaviour, determine resource usage,
712 performance issues or even look for particular execution patterns.
714 This is accomplished by logging the events provided by the Mono
715 runtime through the profiling interface and periodically writing
716 them to a file which can be later inspected with the mprof-report(1)
719 More information about how to use the log profiler is available on the
720 mprof-report(1) page.
722 Mono provides a mechanism for loading other profiling modules which in
723 the form of shared libraries. These profiling modules can hook up to
724 various parts of the Mono runtime to gather information about the code
727 To use a third party profiler you must pass the name of the profiler
731 mono --profile=custom program.exe
735 In the above sample Mono will load the user defined profiler from the
736 shared library `mono-profiler-custom.so'. This profiler module must
737 be on your dynamic linker library path.
739 A list of other third party profilers is available from Mono's web
740 site (www.mono-project.com/docs/advanced/performance-tips/)
742 Custom profiles are written as shared libraries. The shared library
743 must be called `mono-profiler-NAME.so' where `NAME' is the name of
746 For a sample of how to write your own custom profiler look in the
747 Mono source tree for in the samples/profiler.c.
749 Mono ships with a code coverage module. This module is activated by
750 using the Mono --profile=cov option. The format is:
751 \fB--profile=cov[:assembly-name[/namespace]] test-suite.exe\fR
753 By default code coverage will default to all the assemblies loaded,
754 you can limit this by specifying the assembly name, for example to
755 perform code coverage in the routines of your program use, for example
756 the following command line limits the code coverage to routines in the
760 mono --profile=cov:demo demo.exe
766 does not include the extension.
768 You can further restrict the code coverage output by specifying a
772 mono --profile=cov:demo/My.Utilities demo.exe
776 Which will only perform code coverage in the given assembly and
779 Typical output looks like this:
782 Not covered: Class:.ctor ()
783 Not covered: Class:A ()
784 Not covered: Driver:.ctor ()
785 Not covered: Driver:method ()
786 Partial coverage: Driver:Main ()
791 The offsets displayed are IL offsets.
793 A more powerful coverage tool is available in the module `monocov'.
794 See the monocov(1) man page for details.
796 To debug managed applications, you can use the
798 command, a command line debugger.
800 It is possible to obtain a stack trace of all the active threads in
801 Mono by sending the QUIT signal to Mono, you can do this from the
802 command line, like this:
808 Where pid is the Process ID of the Mono process you want to examine.
809 The process will continue running afterwards, but its state is not
813 this is a last-resort mechanism for debugging applications and should
814 not be used to monitor or probe a production application. The
815 integrity of the runtime after sending this signal is not guaranteed
816 and the application might crash or terminate at any given point
819 The \fB--debug=casts\fR option can be used to get more detailed
820 information for Invalid Cast operations, it will provide information
821 about the types involved.
823 You can use the MONO_LOG_LEVEL and MONO_LOG_MASK environment variables
824 to get verbose debugging output about the execution of your
825 application within Mono.
829 environment variable if set, the logging level is changed to the set
830 value. Possible values are "error", "critical", "warning", "message",
831 "info", "debug". The default value is "error". Messages with a logging
832 level greater then or equal to the log level will be printed to
835 Use "info" to track the dynamic loading of assemblies.
840 environment variable to limit the extent of the messages you get:
841 If set, the log mask is changed to the set value. Possible values are
842 "asm" (assembly loader), "type", "dll" (native library loader), "gc"
843 (garbage collector), "cfg" (config file loader), "aot" (precompiler),
844 "security" (e.g. Moonlight CoreCLR support) and "all".
845 The default value is "all". Changing the mask value allows you to display only
846 messages for a certain component. You can use multiple masks by comma
847 separating them. For example to see config file messages and assembly loader
848 messages set you mask to "asm,cfg".
850 The following is a common use to track down problems with P/Invoke:
853 $ MONO_LOG_LEVEL="debug" MONO_LOG_MASK="dll" mono glue.exe
857 .SH DEBUGGING WITH LLDB
858 If you are using LLDB, you can use the
860 script to print some internal data structures with it. To use this,
865 command script import $PREFIX/lib/mono/lldb/mono.py
868 Where $PREFIX is the prefix value that you used when you configured
869 Mono (typically /usr).
871 Once this is done, then you can inspect some Mono Runtime data structures,
876 (MonoMethod *) $0 = 0x05026ac0 [mscorlib]System.OutOfMemoryException:.ctor()
879 Mono's XML serialization engine by default will use a reflection-based
880 approach to serialize which might be slow for continuous processing
881 (web service applications). The serialization engine will determine
882 when a class must use a hand-tuned serializer based on a few
883 parameters and if needed it will produce a customized C# serializer
884 for your types at runtime. This customized serializer then gets
885 dynamically loaded into your application.
887 You can control this with the MONO_XMLSERIALIZER_THS environment
890 The possible values are
892 to disable the use of a C# customized
893 serializer, or an integer that is the minimum number of uses before
894 the runtime will produce a custom serializer (0 will produce a
895 custom serializer on the first access, 50 will produce a serializer on
896 the 50th use). Mono will fallback to an interpreted serializer if the
897 serializer generation somehow fails. This behavior can be disabled
898 by setting the option
900 (for example: MONO_XMLSERIALIZER_THS=0,nofallback).
901 .SH ENVIRONMENT VARIABLES
904 Turns off the garbage collection in Mono. This should be only used
905 for debugging purposes
908 When Mono is compiled with LLVM support, this instructs the runtime to
909 stop using LLVM after the specified number of methods are JITed.
910 This is a tool used in diagnostics to help isolate problems in the
911 code generation backend. For example \fBLLVM_COUNT=10\fR would only
912 compile 10 methods with LLVM and then switch to the Mono JIT engine.
913 \fBLLVM_COUNT=0\fR would disable the LLVM engine altogether.
916 If set, this variable will instruct Mono to ahead-of-time compile new
917 assemblies on demand and store the result into a cache in
920 \fBMONO_ASPNET_INHIBIT_SETTINGSMAP\fR
921 Mono contains a feature which allows modifying settings in the .config files shipped
922 with Mono by using config section mappers. The mappers and the mapping rules are
923 defined in the $prefix/etc/mono/2.0/settings.map file and, optionally, in the
924 settings.map file found in the top-level directory of your ASP.NET application.
925 Both files are read by System.Web on application startup, if they are found at the
926 above locations. If you don't want the mapping to be performed you can set this
927 variable in your environment before starting the application and no action will
930 \fBMONO_ASPNET_WEBCONFIG_CACHESIZE\fR
931 Mono has a cache of ConfigSection objects for speeding up WebConfigurationManager
932 queries. Its default size is 100 items, and when more items are needed, cache
933 evictions start happening. If evictions are too frequent this could impose
934 unnecessary overhead, which could be avoided by using this environment variable
935 to set up a higher cache size (or to lower memory requirements by decreasing it).
937 \fBMONO_CAIRO_DEBUG_DISPOSE\fR
938 If set, causes Mono.Cairo to collect stack traces when objects are allocated,
939 so that the finalization/Dispose warnings include information about the
943 If set, this variable overrides the default system configuration directory
944 ($PREFIX/etc). It's used to locate machine.config file.
947 Sets the style of COM interop. If the value of this variable is "MS"
948 Mono will use string marhsalling routines from the liboleaut32 for the
949 BSTR type library, any other values will use the mono-builtin BSTR
953 If set, this variable overrides the default runtime configuration file
954 ($PREFIX/etc/mono/config). The --config command line options overrides the
955 environment variable.
958 Override the automatic cpu detection mechanism. Currently used only on arm.
959 The format of the value is as follows:
965 where V is the architecture number 4, 5, 6, 7 and the options can be currently be
966 "thumb" or "thumb2". Example:
969 MONO_CPU_ARCH="armv4 thumb" mono ...
973 \fBMONO_ARM_FORCE_SOFT_FLOAT\fR
974 When Mono is built with a soft float fallback on ARM and this variable is set to
975 "1", Mono will always emit soft float code, even if a VFP unit is detected.
977 \fBMONO_DISABLE_AIO\fR
978 If set, tells mono NOT to attempt using native asynchronous I/O services. In
979 that case, a default select/poll implementation is used. Currently only epoll()
982 \fBMONO_DISABLE_MANAGED_COLLATION\fR
983 If this environment variable is `yes', the runtime uses unmanaged
984 collation (which actually means no culture-sensitive collation). It
985 internally disables managed collation functionality invoked via the
986 members of System.Globalization.CompareInfo class. Collation is
989 \fBMONO_DISABLE_SHM\fR
990 Unix only: If set, disables the shared memory files used for
991 cross-process handles: process have only private handles. This means
992 that process and thread handles are not available to other processes,
993 and named mutexes, named events and named semaphores are not visible
996 This is can also be enabled by default by passing the
997 "--disable-shared-handles" option to configure.
999 This is the default from mono 2.8 onwards.
1001 \fBMONO_DISABLE_SHARED_AREA\fR
1002 Unix only: If set, disable usage of shared memory for exposing
1003 performance counters. This means it will not be possible to both
1004 externally read performance counters from this processes or read
1005 those of external processes.
1008 When set, enables the use of a fully managed DNS resolver instead of the
1009 regular libc functions. This resolver performs much better when multiple
1010 queries are run in parallel.
1012 Note that /etc/nsswitch.conf will be ignored.
1014 \fBMONO_EGD_SOCKET\fR
1015 For platforms that do not otherwise have a way of obtaining random bytes
1016 this can be set to the name of a file system socket on which an egd or
1017 prngd daemon is listening.
1019 \fBMONO_ENABLE_SHM\fR
1020 Unix only: Enable support for cross-process handles. Cross-process
1021 handles are used to expose process handles, thread handles, named
1022 mutexes, named events and named semaphores across Unix processes.
1024 \fBMONO_ENV_OPTIONS\fR
1025 This environment variable allows you to pass command line arguments to
1026 a Mono process through the environment. This is useful for example
1027 to force all of your Mono processes to use LLVM or SGEN without having
1028 to modify any launch scripts.
1030 \fBMONO_ENV_OPTIONS\fR
1031 Used to pass extra options to the debugger agent in the runtime, as they were passed
1032 using --debugger-agent=.
1034 \fBMONO_EVENTLOG_TYPE\fR
1035 Sets the type of event log provider to use (for System.Diagnostics.EventLog).
1037 Possible values are:
1042 Persists event logs and entries to the local file system.
1044 The directory in which to persist the event logs, event sources and entries
1045 can be specified as part of the value.
1047 If the path is not explicitly set, it defaults to "/var/lib/mono/eventlog"
1048 on unix and "%APPDATA%\mono\eventlog" on Windows.
1053 Uses the native win32 API to write events and registers event logs and
1054 event sources in the registry. This is only available on Windows.
1056 On Unix, the directory permission for individual event log and event source
1057 directories is set to 777 (with +t bit) allowing everyone to read and write
1058 event log entries while only allowing entries to be deleted by the user(s)
1063 Silently discards any events.
1066 The default is "null" on Unix (and versions of Windows before NT), and
1067 "win32" on Windows NT (and higher).
1070 \fBMONO_EXTERNAL_ENCODINGS\fR
1071 If set, contains a colon-separated list of text encodings to try when
1072 turning externally-generated text (e.g. command-line arguments or
1073 filenames) into Unicode. The encoding names come from the list
1074 provided by iconv, and the special case "default_locale" which refers
1075 to the current locale's default encoding.
1077 When reading externally-generated text strings UTF-8 is tried first,
1078 and then this list is tried in order with the first successful
1079 conversion ending the search. When writing external text (e.g. new
1080 filenames or arguments to new processes) the first item in this list
1081 is used, or UTF-8 if the environment variable is not set.
1083 The problem with using MONO_EXTERNAL_ENCODINGS to process your
1084 files is that it results in a problem: although its possible to get
1085 the right file name it is not necessarily possible to open the file.
1086 In general if you have problems with encodings in your filenames you
1087 should use the "convmv" program.
1089 \fBMONO_GC_PARAMS\fR
1090 When using Mono with the SGen garbage collector this variable controls
1091 several parameters of the collector. The variable's value is a comma
1092 separated list of words.
1096 \fBnursery-size=\fIsize\fR
1097 Sets the size of the nursery. The size is specified in bytes and must
1098 be a power of two. The suffixes `k', `m' and `g' can be used to
1099 specify kilo-, mega- and gigabytes, respectively. The nursery is the
1100 first generation (of two). A larger nursery will usually speed up the
1101 program but will obviously use more memory. The default nursery size
1104 \fBmajor=\fIcollector\fR Specifies which major collector to use.
1105 Options are `marksweep' for the Mark&Sweep collector, and
1106 `marksweep-conc' for concurrent Mark&Sweep. The non-concurrent
1107 Mark&Sweep collector is the default.
1109 \fBsoft-heap-limit=\fIsize\fR
1110 Once the heap size gets larger than this size, ignore what the default
1111 major collection trigger metric says and only allow four nursery size's
1112 of major heap growth between major collections.
1114 \fBevacuation-threshold=\fIthreshold\fR
1115 Sets the evacuation threshold in percent. This option is only available
1116 on the Mark&Sweep major collectors. The value must be an
1117 integer in the range 0 to 100. The default is 66. If the sweep phase of
1118 the collection finds that the occupancy of a specific heap block type is
1119 less than this percentage, it will do a copying collection for that block
1120 type in the next major collection, thereby restoring occupancy to close
1121 to 100 percent. A value of 0 turns evacuation off.
1123 \fB(no-)lazy-sweep\fR
1124 Enables or disables lazy sweep for the Mark&Sweep collector. If
1125 enabled, the sweep phase of the garbage collection is done piecemeal
1126 whenever the need arises, typically during nursery collections. Lazy
1127 sweeping is enabled by default.
1129 \fBstack-mark=\fImark-mode\fR
1130 Specifies how application threads should be scanned. Options are
1131 `precise` and `conservative`. Precise marking allow the collector
1132 to know what values on stack are references and what are not.
1133 Conservative marking threats all values as potentially references
1134 and leave them untouched. Precise marking reduces floating garbage
1135 and can speed up nursery collection and allocation rate, it has
1136 the downside of requiring a significant extra memory per compiled
1137 method. The right option, unfortunately, requires experimentation.
1139 \fBsave-target-ratio=\fIratio\fR
1140 Specifies the target save ratio for the major collector. The collector
1141 lets a given amount of memory to be promoted from the nursery due to
1142 minor collections before it triggers a major collection. This amount
1143 is based on how much memory it expects to free. It is represented as
1144 a ratio of the size of the heap after a major collection.
1145 Valid values are between 0.1 and 2.0. The default is 0.5.
1146 Smaller values will keep the major heap size smaller but will trigger
1147 more major collections. Likewise, bigger values will use more memory
1148 and result in less frequent major collections.
1149 This option is EXPERIMENTAL, so it might disappear in later versions of mono.
1151 \fBdefault-allowance-ratio=\fIratio\fR
1152 Specifies the default allocation allowance when the calculated size
1153 is too small. The allocation allowance is how much memory the collector
1154 let be promoted before triggered a major collection.
1155 It is a ratio of the nursery size.
1156 Valid values are between 1.0 and 10.0. The default is 4.0.
1157 Smaller values lead to smaller heaps and more frequent major collections.
1158 Likewise, bigger values will allow the heap to grow faster but use
1159 more memory when it reaches a stable size.
1160 This option is EXPERIMENTAL, so it might disappear in later versions of mono.
1162 \fBminor=\fIminor-collector\fR
1163 Specifies which minor collector to use. Options are 'simple' which
1164 promotes all objects from the nursery directly to the old generation
1165 and 'split' which lets object stay longer on the nursery before promoting.
1167 \fBalloc-ratio=\fIratio\fR
1168 Specifies the ratio of memory from the nursery to be use by the alloc space.
1169 This only can only be used with the split minor collector.
1170 Valid values are integers between 1 and 100. Default is 60.
1172 \fBpromotion-age=\fIage\fR
1173 Specifies the required age of an object must reach inside the nursery before
1174 been promoted to the old generation. This only can only be used with the
1175 split minor collector.
1176 Valid values are integers between 1 and 14. Default is 2.
1178 \fB(no-)cementing\fR
1179 Enables or disables cementing. This can dramatically shorten nursery
1180 collection times on some benchmarks where pinned objects are referred
1181 to from the major heap.
1186 When using Mono with the SGen garbage collector this environment
1187 variable can be used to turn on various debugging features of the
1188 collector. The value of this variable is a comma separated list of
1189 words. Do not use these options in production.
1194 Sets the debug level to the specified number.
1196 \fBprint-allowance\fR
1197 After each major collection prints memory consumption for before and
1198 after the collection and the allowance for the minor collector, i.e. how
1199 much the heap is allowed to grow from minor collections before the next
1200 major collection is triggered.
1203 Gathers statistics on the classes whose objects are pinned in the
1204 nursery and for which global remset entries are added. Prints those
1205 statistics when shutting down.
1207 \fBcollect-before-allocs\fR
1209 \fBcheck-at-minor-collections\fR
1210 This performs a consistency check on minor collections and also clears
1211 the nursery at collection time, instead of the default, when buffers
1212 are allocated (clear-at-gc). The consistency check ensures that
1213 there are no major to minor references that are not on the remembered
1216 \fBmod-union-consistency-check\fR
1217 Checks that the mod-union cardtable is consistent before each
1218 finishing major collection pause. This check is only applicable to
1219 concurrent major collectors.
1221 \fBcheck-mark-bits\fR
1222 Checks that mark bits in the major heap are consistent at the end of
1223 each major collection. Consistent mark bits mean that if an object is
1224 marked, all objects that it had references to must also be marked.
1226 \fBcheck-nursery-pinned\fR
1227 After nursery collections, and before starting concurrent collections,
1228 check whether all nursery objects are pinned, or not pinned -
1229 depending on context. Does nothing when the split nursery collector
1232 \fBxdomain-checks\fR
1233 Performs a check to make sure that no references are left to an
1236 \fBclear-at-tlab-creation\fR
1237 Clears the nursery incrementally when the thread local allocation
1238 buffers (TLAB) are created. The default setting clears the whole
1241 \fBdebug-clear-at-tlab-creation\fR
1242 Clears the nursery incrementally when the thread local allocation
1243 buffers (TLAB) are created, but at GC time fills it with the byte
1244 `0xff`, which should result in a crash more quickly if
1245 `clear-at-tlab-creation` doesn't work properly.
1248 This clears the nursery at GC time instead of doing it when the thread
1249 local allocation buffer (TLAB) is created. The default is to clear
1250 the nursery at TLAB creation time.
1253 Don't do minor collections. If the nursery is full, a major collection
1254 is triggered instead, unless it, too, is disabled.
1257 Don't do major collections.
1259 \fBconservative-stack-mark\fR
1260 Forces the GC to scan the stack conservatively, even if precise
1261 scanning is available.
1263 \fBno-managed-allocator\fR
1264 Disables the managed allocator.
1266 \fBcheck-scan-starts\fR
1267 If set, does a plausibility check on the scan_starts before and after each collection
1269 \fBverify-nursery-at-minor-gc\fR
1270 If set, does a complete object walk of the nursery at the start of each minor collection.
1272 \fBdump-nursery-at-minor-gc\fR
1273 If set, dumps the contents of the nursery at the start of each minor collection. Requires
1274 verify-nursery-at-minor-gc to be set.
1276 \fBheap-dump=\fIfile\fR
1277 Dumps the heap contents to the specified file. To visualize the
1278 information, use the mono-heapviz tool.
1280 \fBbinary-protocol=\fIfile\fR
1281 Outputs the debugging output to the specified file. For this to
1282 work, Mono needs to be compiled with the BINARY_PROTOCOL define on
1283 sgen-gc.c. You can then use this command to explore the output
1285 sgen-grep-binprot 0x1234 0x5678 < file
1288 \fBnursery-canaries\fR
1289 If set, objects allocated in the nursery are suffixed with a canary (guard)
1290 word, which is checked on each minor collection. Can be used to detect/debug
1291 heap corruption issues.
1294 \fBdo-not-finalize\fR
1295 If enabled, finalizers will not be run. Everything else will be
1296 unaffected: finalizable objects will still be put into the
1297 finalization queue where they survive until they're scheduled to
1298 finalize. Once they're not in the queue anymore they will be
1299 collected regularly.
1302 \fBlog-finalizers\fR
1303 Log verbosely around the finalization process to aid debugging.
1307 \fBMONO_GAC_PREFIX\fR
1308 Provides a prefix the runtime uses to look for Global Assembly Caches.
1309 Directories are separated by the platform path separator (colons on
1310 unix). MONO_GAC_PREFIX should point to the top directory of a prefixed
1311 install. Or to the directory provided in the gacutil /gacdir command. Example:
1312 .B /home/username/.mono:/usr/local/mono/
1315 Enables some filename rewriting support to assist badly-written
1316 applications that hard-code Windows paths. Set to a colon-separated
1317 list of "drive" to strip drive letters, or "case" to do
1318 case-insensitive file matching in every directory in a path. "all"
1319 enables all rewriting methods. (Backslashes are always mapped to
1320 slashes if this variable is set to a valid option).
1323 For example, this would work from the shell:
1326 MONO_IOMAP=drive:case
1330 If you are using mod_mono to host your web applications, you can use
1333 directive instead, like this:
1336 MonoIOMAP <appalias> all
1339 See mod_mono(8) for more details.
1341 Additionally. Mono includes a profiler module which allows one to track what
1342 adjustements to file paths IOMAP code needs to do. The tracking code reports
1343 the managed location (full stack trace) from which the IOMAP-ed call was made and,
1344 on process exit, the locations where all the IOMAP-ed strings were created in
1345 managed code. The latter report is only approximate as it is not always possible
1346 to estimate the actual location where the string was created. The code uses simple
1347 heuristics - it analyzes stack trace leading back to the string allocation location
1348 and ignores all the managed code which lives in assemblies installed in GAC as well as in the
1349 class libraries shipped with Mono (since they are assumed to be free of case-sensitivity
1350 issues). It then reports the first location in the user's code - in most cases this will be
1351 the place where the string is allocated or very close to the location. The reporting code
1352 is implemented as a custom profiler module (see the "PROFILING" section) and can be loaded
1353 in the following way:
1358 mono --profile=iomap yourapplication.exe
1361 Note, however, that Mono currently supports only one profiler module
1365 When Mono is using the LLVM code generation backend you can use this
1366 environment variable to pass code generation options to the LLVM
1369 \fBMONO_MANAGED_WATCHER\fR
1370 If set to "disabled", System.IO.FileSystemWatcher will use a file watcher
1371 implementation which silently ignores all the watching requests.
1372 If set to any other value, System.IO.FileSystemWatcher will use the default
1373 managed implementation (slow). If unset, mono will try to use inotify, FAM,
1374 Gamin, kevent under Unix systems and native API calls on Windows, falling
1375 back to the managed implementation on error.
1377 \fBMONO_MESSAGING_PROVIDER\fR
1378 Mono supports a plugin model for its implementation of System.Messaging making
1379 it possible to support a variety of messaging implementations (e.g. AMQP, ActiveMQ).
1380 To specify which messaging implementation is to be used the evironement variable
1381 needs to be set to the full class name for the provider. E.g. to use the RabbitMQ based
1382 AMQP implementation the variable should be set to:
1385 Mono.Messaging.RabbitMQ.RabbitMQMessagingProvider,Mono.Messaging.RabbitMQ
1388 If set causes the mono process to be bound to a single processor. This may be
1389 useful when debugging or working around race conditions.
1392 Disable inlining of thread local accesses. Try setting this if you get a segfault
1393 early on in the execution of mono.
1396 Provides a search path to the runtime where to look for library
1397 files. This is a tool convenient for debugging applications, but
1398 should not be used by deployed applications as it breaks the assembly
1399 loader in subtle ways.
1401 Directories are separated by the platform path separator (colons on unix). Example:
1402 .B /home/username/lib:/usr/local/mono/lib
1404 Relative paths are resolved based on the launch-time current directory.
1406 Alternative solutions to MONO_PATH include: installing libraries into
1407 the Global Assembly Cache (see gacutil(1)) or having the dependent
1408 libraries side-by-side with the main executable.
1410 For a complete description of recommended practices for application
1412 http://www.mono-project.com/docs/getting-started/application-deployment/
1415 Experimental RTC support in the statistical profiler: if the user has
1416 the permission, more accurate statistics are gathered. The MONO_RTC
1417 value must be restricted to what the Linux rtc allows: power of two
1418 from 64 to 8192 Hz. To enable higher frequencies like 4096 Hz, run as root:
1421 echo 4096 > /proc/sys/dev/rtc/max-user-freq
1428 MONO_RTC=4096 mono --profiler=default:stat program.exe
1432 \fBMONO_SHARED_DIR\fR
1433 If set its the directory where the ".wapi" handle state is stored.
1434 This is the directory where the Windows I/O Emulation layer stores its
1435 shared state data (files, events, mutexes, pipes). By default Mono
1436 will store the ".wapi" directory in the users's home directory.
1438 \fBMONO_SHARED_HOSTNAME\fR
1439 Uses the string value of this variable as a replacement for the host name when
1440 creating file names in the ".wapi" directory. This helps if the host name of
1441 your machine is likely to be changed when a mono application is running or if
1442 you have a .wapi directory shared among several different computers.
1444 Mono typically uses the hostname to create the files that are used to
1445 share state across multiple Mono processes. This is done to support
1446 home directories that might be shared over the network.
1448 \fBMONO_STRICT_IO_EMULATION\fR
1449 If set, extra checks are made during IO operations. Currently, this
1450 includes only advisory locks around file writes.
1453 The name of the theme to be used by Windows.Forms. Available themes today
1454 include "clearlooks", "nice" and "win32".
1456 The default is "win32".
1458 \fBMONO_TLS_SESSION_CACHE_TIMEOUT\fR
1459 The time, in seconds, that the SSL/TLS session cache will keep it's entry to
1460 avoid a new negotiation between the client and a server. Negotiation are very
1461 CPU intensive so an application-specific custom value may prove useful for
1462 small embedded systems.
1464 The default is 180 seconds.
1466 \fBMONO_THREADS_PER_CPU\fR
1467 The minimum number of threads in the general threadpool will be
1468 MONO_THREADS_PER_CPU * number of CPUs. The default value for this
1471 \fBMONO_XMLSERIALIZER_THS\fR
1472 Controls the threshold for the XmlSerializer to produce a custom
1473 serializer for a given class instead of using the Reflection-based
1474 interpreter. The possible values are `no' to disable the use of a
1475 custom serializer or a number to indicate when the XmlSerializer
1476 should start serializing. The default value is 50, which means that
1477 the a custom serializer will be produced on the 50th use.
1479 \fBMONO_X509_REVOCATION_MODE\fR
1480 Sets the revocation mode used when validating a X509 certificate chain (https,
1481 ftps, smtps...). The default is 'nocheck', which performs no revocation check
1482 at all. The other possible values are 'offline', which performs CRL check (not
1483 implemented yet) and 'online' which uses OCSP and CRL to verify the revocation
1484 status (not implemented yet).
1485 .SH ENVIRONMENT VARIABLES FOR DEBUGGING
1487 \fBMONO_ASPNET_NODELETE\fR
1488 If set to any value, temporary source files generated by ASP.NET support
1489 classes will not be removed. They will be kept in the user's temporary
1493 If set, enables some features of the runtime useful for debugging.
1494 This variable should contain a comma separated list of debugging options.
1495 Currently, the following options are supported:
1499 \fBbreak-on-unverified\fR
1500 If this variable is set, when the Mono VM runs into a verification
1501 problem, instead of throwing an exception it will break into the
1502 debugger. This is useful when debugging verifier problems
1505 This option can be used to get more detailed information from
1506 InvalidCast exceptions, it will provide information about the types
1509 \fBcollect-pagefault-stats\fR
1510 Collects information about pagefaults. This is used internally to
1511 track the number of page faults produced to load metadata. To display
1512 this information you must use this option with "--stats" command line
1515 \fBdont-free-domains\fR
1516 This is an Optimization for multi-AppDomain applications (most
1517 commonly ASP.NET applications). Due to internal limitations Mono,
1518 Mono by default does not use typed allocations on multi-appDomain
1519 applications as they could leak memory when a domain is unloaded.
1521 Although this is a fine default, for applications that use more than
1522 on AppDomain heavily (for example, ASP.NET applications) it is worth
1523 trading off the small leaks for the increased performance
1524 (additionally, since ASP.NET applications are not likely going to
1525 unload the application domains on production systems, it is worth
1526 using this feature).
1528 \fBdyn-runtime-invoke\fR
1529 Instructs the runtime to try to use a generic runtime-invoke wrapper
1530 instead of creating one invoke wrapper.
1533 Equivalent to setting the \fBMONO_XDEBUG\fR variable, this emits
1534 symbols into a shared library as the code is JITed that can be loaded
1535 into GDB to inspect symbols.
1537 \fBgen-seq-points\fR
1538 Automatically generates sequence points where the
1539 IL stack is empty. These are places where the debugger can set a
1542 \fBexplicit-null-checks\fR
1543 Makes the JIT generate an explicit NULL check on variable dereferences
1544 instead of depending on the operating system to raise a SIGSEGV or
1545 another form of trap event when an invalid memory location is
1549 Captures the interrupt signal (Control-C) and displays a stack trace
1550 when pressed. Useful to find out where the program is executing at a
1551 given point. This only displays the stack trace of a single thread.
1554 Instructs the runtime to initialize the stack with
1555 some known values (0x2a on x86-64) at the start of a method to assist
1556 in debuggin the JIT engine.
1558 \fBkeep-delegates\fR
1559 This option will leak delegate trampolines that are no longer
1560 referenced as to present the user with more information about a
1561 delegate misuse. Basically a delegate instance might be created,
1562 passed to unmanaged code, and no references kept in managed code,
1563 which will garbage collect the code. With this option it is possible
1564 to track down the source of the problems.
1566 \fBreverse-pinvoke-exceptions
1567 This option will cause mono to abort with a descriptive message when
1568 during stack unwinding after an exception it reaches a native stack
1569 frame. This happens when a managed delegate is passed to native code,
1570 and the managed delegate throws an exception. Mono will normally try
1571 to unwind the stack to the first (managed) exception handler, and it
1572 will skip any native stack frames in the process. This leads to
1573 undefined behaviour (since mono doesn't know how to process native
1574 frames), leaks, and possibly crashes too.
1576 \fBno-gdb-backtrace\fR
1577 This option will disable the GDB backtrace emitted by the runtime
1578 after a SIGSEGV or SIGABRT in unmanaged code.
1580 \fBsuspend-on-sigsegv\fR
1581 This option will suspend the program when a native SIGSEGV is received.
1582 This is useful for debugging crashes which do not happen under gdb,
1583 since a live process contains more information than a core file.
1585 \fBcheck-pinvoke-callconv\fR
1586 This option causes the runtime to check for calling convention
1587 mismatches when using pinvoke, i.e. mixing cdecl/stdcall. It only
1588 works on windows. If a mismatch is detected, an
1589 ExecutionEngineException is thrown.
1593 \fBMONO_LOG_LEVEL\fR
1594 The logging level, possible values are `error', `critical', `warning',
1595 `message', `info' and `debug'. See the DEBUGGING section for more
1599 Controls the domain of the Mono runtime that logging will apply to.
1600 If set, the log mask is changed to the set value. Possible values are
1601 "asm" (assembly loader), "type", "dll" (native library loader), "gc"
1602 (garbage collector), "cfg" (config file loader), "aot" (precompiler),
1603 "security" (e.g. Moonlight CoreCLR support) and "all".
1604 The default value is "all". Changing the mask value allows you to display only
1605 messages for a certain component. You can use multiple masks by comma
1606 separating them. For example to see config file messages and assembly loader
1607 messages set you mask to "asm,cfg".
1610 Used for runtime tracing of method calls. The format of the comma separated
1619 disabled Trace output off upon start.
1622 You can toggle trace output on/off sending a SIGUSR2 signal to the program.
1624 \fBMONO_TRACE_LISTENER\fR
1625 If set, enables the System.Diagnostics.DefaultTraceListener, which will
1626 print the output of the System.Diagnostics Trace and Debug classes.
1627 It can be set to a filename, and to Console.Out or Console.Error to display
1628 output to standard output or standard error, respectively. If it's set to
1629 Console.Out or Console.Error you can append an optional prefix that will
1630 be used when writing messages like this: Console.Error:MyProgramName.
1631 See the System.Diagnostics.DefaultTraceListener documentation for more
1634 \fBMONO_WCF_TRACE\fR
1635 This eases WCF diagnostics functionality by simply outputs all log messages from WCF engine to "stdout", "stderr" or any file passed to this environment variable. The log format is the same as usual diagnostic output.
1637 \fBMONO_XEXCEPTIONS\fR
1638 This throws an exception when a X11 error is encountered; by default a
1639 message is displayed but execution continues
1641 \fBMONO_XMLSERIALIZER_DEBUG\fR
1642 Set this value to 1 to prevent the serializer from removing the
1643 temporary files that are created for fast serialization; This might
1644 be useful when debugging.
1647 This is used in the System.Windows.Forms implementation when running
1648 with the X11 backend. This is used to debug problems in Windows.Forms
1649 as it forces all of the commands send to X11 server to be done
1650 synchronously. The default mode of operation is asynchronous which
1651 makes it hard to isolate the root of certain problems.
1653 \fBMONO_GENERIC_SHARING\fR
1654 This environment variable controls the kind of generic sharing used.
1655 This variable is used by internal JIT developers and should not be
1656 changed in production. Do not use it.
1658 The variable controls which classes will have generic code sharing
1661 Permissible values are:
1665 All generated code can be shared.
1668 Only the classes in System.Collections.Generic will have its code
1669 shared (this is the default value).
1672 Only code in corlib will have its code shared.
1675 No generic code sharing will be performed.
1678 Generic code sharing by default only applies to collections. The
1679 Mono JIT by default turns this on.
1682 When the the MONO_XDEBUG env var is set, debugging info for JITted
1683 code is emitted into a shared library, loadable into gdb. This enables,
1684 for example, to see managed frame names on gdb backtraces.
1686 \fBMONO_VERBOSE_METHOD\fR
1687 Enables the maximum JIT verbosity for the specified method. This is
1688 very helpfull to diagnose a miscompilation problems of a specific
1691 \fBMONO_VERBOSE_HWCAP\fR
1692 If set, makes the JIT output information about detected CPU features
1693 (such as SSE, CMOV, FCMOV, etc) to stdout.
1695 \fBMONO_CONSERVATIVE_HWCAP\fR
1696 If set, the JIT will not perform any hardware capability detection. This
1697 may be useful to pinpoint the cause of JIT issues. This is the default
1698 when Mono is built as an AOT cross compiler, so that the generated code
1699 will run on most hardware.
1701 If you want to use Valgrind, you will find the file `mono.supp'
1702 useful, it contains the suppressions for the GC which trigger
1703 incorrect warnings. Use it like this:
1705 valgrind --suppressions=mono.supp mono ...
1708 On some platforms, Mono can expose a set of DTrace probes (also known
1709 as user-land statically defined, USDT Probes).
1711 They are defined in the file `mono.d'.
1713 .B ves-init-begin, ves-init-end
1715 Begin and end of runtime initialization.
1717 .B method-compile-begin, method-compile-end
1719 Begin and end of method compilation.
1720 The probe arguments are class name, method name and signature,
1721 and in case of method-compile-end success or failure of compilation.
1725 Begin and end of Garbage Collection.
1727 To verify the availability of the probes, run:
1729 dtrace -P mono'$target' -l -c mono
1732 Mono's Ping implementation for detecting network reachability can
1733 create the ICMP packets itself without requiring the system ping
1734 command to do the work. If you want to enable this on Linux for
1735 non-root users, you need to give the Mono binary special permissions.
1737 As root, run this command:
1739 # setcap cap_net_raw=+ep /usr/bin/mono
1742 On Unix assemblies are loaded from the installation lib directory. If you set
1743 `prefix' to /usr, the assemblies will be located in /usr/lib. On
1744 Windows, the assemblies are loaded from the directory where mono and
1747 .B ~/.mono/aot-cache
1749 The directory for the ahead-of-time compiler demand creation
1750 assemblies are located.
1752 .B /etc/mono/config, ~/.mono/config
1754 Mono runtime configuration file. See the mono-config(5) manual page
1755 for more information.
1757 .B ~/.config/.mono/certs, /usr/share/.mono/certs
1759 Contains Mono certificate stores for users / machine. See the certmgr(1)
1760 manual page for more information on managing certificate stores and
1761 the mozroots(1) page for information on how to import the Mozilla root
1762 certificates into the Mono certificate store.
1764 .B ~/.mono/assemblies/ASSEMBLY/ASSEMBLY.config
1766 Files in this directory allow a user to customize the configuration
1767 for a given system assembly, the format is the one described in the
1768 mono-config(5) page.
1770 .B ~/.config/.mono/keypairs, /usr/share/.mono/keypairs
1772 Contains Mono cryptographic keypairs for users / machine. They can be
1773 accessed by using a CspParameters object with DSACryptoServiceProvider
1774 and RSACryptoServiceProvider classes.
1776 .B ~/.config/.isolatedstorage, ~/.local/share/.isolatedstorage, /usr/share/.isolatedstorage
1778 Contains Mono isolated storage for non-roaming users, roaming users and
1779 local machine. Isolated storage can be accessed using the classes from
1780 the System.IO.IsolatedStorage namespace.
1782 .B <assembly>.config
1784 Configuration information for individual assemblies is loaded by the
1785 runtime from side-by-side files with the .config files, see the
1786 http://www.mono-project.com/Config for more information.
1788 .B Web.config, web.config
1790 ASP.NET applications are configured through these files, the
1791 configuration is done on a per-directory basis. For more information
1792 on this subject see the http://www.mono-project.com/Config_system.web
1795 Mailing lists are listed at the
1796 http://www.mono-project.com/community/help/mailing-lists/
1798 http://www.mono-project.com
1801 certmgr(1), csharp(1), mcs(1), mdb(1), monocov(1), monodis(1),
1802 mono-config(5), mozroots(1), mprof-report(1), pdb2mdb(1), xsp(1), mod_mono(8).
1804 For more information on AOT:
1805 http://www.mono-project.com/docs/advanced/aot/
1807 For ASP.NET-related documentation, see the xsp(1) manual page
projects / mono.git / blob