.\" Author:
.\" Miguel de Icaza (miguel@gnu.org)
.\"
-.de Sp \" Vertical space (when we can't use .PP)
-.if t .sp .5v
-.if n .sp
-..
-.TH Mono "Mono 1.0"
+.TH Mono "Mono 2.2"
.SH NAME
mono \- Mono's ECMA-CLI native code generator (Just-in-Time and Ahead-of-Time)
.SH SYNOPSIS
.TP
.I write-symbols
Instructs the AOT compiler to emit debug symbol information.
+.TP
+.I static
+Create an ELF object file (.o) which can be statically linked into an executable
+when embedding the mono runtime. When this option is used, the object file needs to
+be registered with the embedded runtime using the mono_aot_register_module function
+which takes as its argument the mono_aot_module_<ASSEMBLY NAME>_info global symbol
+from the object file:
+
+.nf
+extern void *mono_aot_module_hello_info;
+
+mono_aot_register_module (mono_aot_module_hello_info);
+.fi
.ne
-.RE
-.Sp
+
+.PP
For more information about AOT, see: http://www.mono-project.com/AOT
+.RE
.TP
-\fB--aot-only\fR
+\fB--attach=[options]\fR
+Currently the only option supported by this command line argument is
+\fBdisable\fR which disables the attach functionality.
+.TP
+\fB--full-aot\fR
This is an experimental flag that instructs the Mono runtime to not
generate any code at runtime and depend exclusively on the code
generated from using mono --aot=full previously. This is useful for
abcrem Array bound checks removal
ssapre SSA based Partial Redundancy Elimination
sse2 SSE2 instructions on x86 [arch-dependency]
+ gshared Enable generic code sharing.
.fi
.Sp
For example, to enable all the optimization but dead code
not allow managed code to crash mono. The verification is not as
strict as ECMA 335 standard in order to stay compatible with the MS
runtime.
+.PP
+The security system acts on user code: code contained in mscorlib or
+the global assembly cache is always trusted.
.ne
.RE
.TP
Configures the virtual machine to be better suited for server
operations (currently, a no-op).
.TP
+\fB--verify-all\fR
+Verifies mscorlib and assemblies in the global
+assembly cache for valid IL, and all user code for IL
+verifiability.
+
+This is different from \fB--security\fR's verifiable
+or validil in that these options only check user code and skip
+mscorlib and assemblies located on the global assembly cache.
+.TP
\fB-V\fR, \fB--version\fR
Prints JIT version information (system configuration, release number
and branch names if available).
The following options are supported:
.TP
.I casts
-Produces a detailed error when throwing a InvalidCastException.
+Produces a detailed error when throwing a InvalidCastException. This
+option needs to be enabled as this generates more verbose code at
+execution time.
.TP
.I mdb-optimizations
Disable some JIT optimizations which are usually only disabled when
mono --trace=N:System.Xml
.fi
+.TP
+\fB--no-x86-stack-align\fR
+Don't align stack frames on the x86 architecture. By default, Mono
+aligns stack frames to 16 bytes on x86, so that local floating point
+and SIMD variables can be properly aligned. This option turns off the
+alignment, which usually saves one intruction per call, but might
+result in significantly lower floating point and SIMD performance.
.SH JIT MAINTAINER OPTIONS
The maintainer options are only used by those developing the runtime
itself, and not typically of interest to runtime users or developers.
Increases the verbosity level, each time it is listed, increases the
verbosity level to include more information (including, for example,
a disassembly of the native code produced, code selector info etc.).
+.SH ATTACH SUPPORT
+The Mono runtime allows external processes to attach to a running
+process and load assemblies into the running program. To attach to
+the process, a special protocol is implemented in the Mono.Management
+assembly.
+.PP
+With this support it is possible to load assemblies that have an entry
+point (they are created with -target:exe or -target:winexe) to be
+loaded and executed in the Mono process.
+.PP
+The code is loaded into the root domain, and it starts execution on
+the special runtime attach thread. The attached program should
+create its own threads and return after invocation.
+.PP
+This support allows for example debugging applications by having the
+csharp shell attach to running processes.
.SH PROFILING
The mono runtime includes a profiler that can be used to explore
various performance related problems in your application. The
The
.I logging profiler
will eventually replace the default profiler as it is more complete
-and encompasses the functionality of all the other profiler for Mono.
-It is able to track method execution times, allocations, jit times and
-collect statistical data. Instead of reporting the collected
-information at the end of the execution of the program, it logs these
-events periodically into a file during program execution. The output
-file contains compressed events, to process the data you should use
-tools like the "Mono.Profiler" tool provided on the Mono SVN
+and encompasses the functionality of all the other profilers for Mono.
+It supports the following execution modes:
+.IP
+.I Statistical:
+the program instruction pointer is periodically sampled (it works also with
+unmanaged functions). If call chains are requested, for each sample the
+profiler gets a partial stack trace (up to a desired depth) so that
+caller-callee information is available.
+.IP
+.I Instrumenting:
+each method enter and exit is logged with a timestamp; further processing of
+the data can show the methods that took the longer to execute, with complete
+accounting for callers and callees. However, this way of profiling is rather
+intrusive and slows down the application significantly.
+.IP
+.I Allocation:
+each allocation is logged.
+.IP
+.I Allocation summary:
+shows, for each collection, a summary of the heap contents broken down by
+class (for each class the number of allocated and released objects is
+given, together with their aggregated size in bytes).
+.IP
+.I Heap snapshot mode:
+dumps the whole heap contents at every collection (or at user specified
+collections). It is also possible to request a collection and snapshot dump
+with a signal.
+.PP
+Moreover, other events can be logged and analyzed, like jit time for each
+method, load and unload for assemblies, modules and and individual classes,
+and appdomain and thread creation and destruction.
+.PP
+Instead of reporting the collected
+information at the end of the execution of the program, this profiler logs
+all the events periodically into a file during program execution.
+To minimize the performance impact with multi-threaded applications,
+the logging uses per-thread buffers that are routinely saved to disk.
+.PP
+The output file contains compressed events, to process the data you should
+use tools like the "Mono.Profiler" tool provided on the Mono SVN
repository.
+.PP
+This profiler is activated passing the \fB--profile=logging\fR option to
+the mono runtime, and is controlled attaching further options, like
+\fB--profile=logging:statistical\fR for doing statistical profiling (multiple
+options are separated by commas).
+.PP
+As a quick primer, here are a few examples of the most common usage modes:
+.PP
+To write the resulting data to "mydata.mprof" (defaults to statistical
+profiling):
.nf
- mono --profile=logging[:OPTIONS] program.exe
+ mono --profile=logging:output=mydata.mprof program.exe
+.fi
+.PP
+To perform statistical profiling, inspecting call chains up to depth 8:
+.nf
+ mono --profile=logging:statistical=8 program.exe
.fi
.PP
-To minimize the performance impact with multi-threaded applications,
-the logging profiler keeps a per-thread buffer that is routinely saved
-to disk.
+To profile allocations (by default the call stack will be analized for
+each allocation, producing detailed caller method attribution infornation):
+.nf
+
+ mono --profile=logging:allocations program.exe
+.fi
+.PP
+To profile garbage collection activity at a high level (collection time and objects freed
+at each collection for each class are reported, but heap snapshots are not saved to disk):
+.nf
+
+ mono --profile=logging:allocations-summary program.exe
+.fi
+.PP
+To perform heap profiling taking heap snapshots:
+.nf
+
+ mono --profile=logging:heap=all program.exe
+ mono --profile=logging:heap=<signal> program.exe
+.fi
+
+If "all" is specified, a heap snapshot is taken at each collection.
+If, instead, a signal name or number is given (one of SIGUSR1, SIGUSR2 and
+SIGPROF, remembering that SIGPROF is not compatible with the statistical
+profiler), a garbage collection is forced and a snapshot is taken every
+time the signal is received.
+Heap profiling also enables full allocation profiling (with call stacks),
+and each allocation can be related to its corresponding object in the
+snapshots, enabling investigations like "find all objects of a given class
+allocated by a given method and still live at a given collection, and then
+find all objects referencing them".
+
.PP
-If specified, the options are separated by commas:
+Then you would need to invoke the decoder \fImprof-decoder(1)\fR
+on the output file to see the profiling results, or to examine heap
+snapshots and allocations in detail \fImprof-heap-viewer(1)\fR.
+
+.PP
+The operating modes described above are the default ones, and are sufficient
+to use the profiler.
+.PP
+To further customize the profiler behavior there are more options, described
+below.
+These options can be individually enabled and disabled prefixing them with
+an (optional) '+' character or a '-' character.
+For instance, the "allocations" option by default records also the full call
+stack at each allocation.
+If only the caller is wanted, one should use "allocations,-save-allocation-stack",
+or to disable call tracking completely (making the profiler less intrusive)
+"allocations,-save-allocation-caller,-save-allocation-stack".
+In practice the "allocation" option by default behaves like
+"allocations,save-allocation-caller,save-allocation-stack", but the user can
+tune this to his needs.
+.PP
+These are all the available options, organized by category:
+.PP
+\fBExecution profiling modes\fR
.RS
.ne 8
.TP
-\fIoutput=FILE\fR, \fIout=FILE\fR or \fIo=FILE\fR
-Use this option to provide the output file name for the profile log.
-If this option is not specified, it will default to profiler-log.prof.
-.TP
-\fIjit\fR, \fIj\fR
-Collect information about time spent by the JIT engine compiling
-methods.
-.TP
-\fIallocations\fR, \fIalloc\fR or \fIa\fR Collect
-information about each allocation (object class and size).
+\fIstatistical\fR, \fIstat\fR or \fIs\fR
+Performs statistical profiling. This is a lightweight profiling
+mechanism and it has a much lower overhead than the \fIenter-leave\fR
+profiling as it works by sampling where the program is spending its
+time by using a timer.
+If specified with \fIs=<number>\fR, also inspect call chains up to level
+<number>.
.TP
\fIenter-leave\fR, \fIcalls\fR or \fIc\fR
Measure the time spent inside each method call, this is done by
logging the time when a method enters and when the method leaves.
This can be a time consuming operation.
.TP
-\fIstatistical\fR, \fIstat\fR or \fIs\fR
-Performs statistical profiling. This is a lightweight profiling
-mechanism as it has a much lower overhead than the \fIenter-leave\fR
-profiling as it works by sampling where the program is spending its
-time by using a timer.
+\fIjit\fR, \fIj\fR
+Collect information about time spent by the JIT engine compiling
+methods.
+.ne
+.RE
+.PP
+\fBAllocation profiling modes\fR
+.RS
+.ne 8
+.TP
+\fIallocations\fR, \fIalloc\fR or \fIa\fR
+Collect information about each allocation (object class and size).
+By default this also implies "+save-allocation-caller" and
+"+save-allocation-stack".
+.TP
+\fIsave-allocation-caller\fR, \fIsac\fR
+Save the direct caller of each allocation. The profiler filters out wrapper
+methods, and also recognizes if the allocation has been performed by the
+runtime while jitting a method.
+.TP
+\fIsave-allocation-stack\fR, \fIsas\fR
+Save the full managed execution stack at each allocation.
+While the "sac" option saves the direct caller, this one records the whole
+stack trace.
+Note that in the call stack the wrapper methods are not filtered out.
+Anyway the "sac" and "sas" options can be combined, and the decoder will
+attribute the allocation to the correct method even if the wrapper is at the
+top of the stack trace.
+.TP
+\fIallocations-summary\fR or \fIas\fR
+At each collection dump a summary
+of the heap contents (for each class, the number and collective size of all
+live and freed heap objects). This very lightweight compared to full heap
+snapshots.
.TP
\fIunreachable\fR, \fIfree\fR or \fIf\fR
-Performs a lighweight profile of the garbage collector. On each
+Performs a lightweight profile of the garbage collector. On each
collection performed by the GC, the list of unreachable objects is
recorded, and for each object the class and size is provided. This
-information is useful to compute the heap size broken down by class.
+information can be used to compute the heap size broken down by class
+(combined with "a" can give the same information of "as", but the log
+file contains info about each individual object, while in "as" the
+processing is done directly at runtime and the log file contains only
+the summarized data broken down by class).
+.TP
+\fIgc\fR or \fIg\fR
+Measure the time spent in each collection, and also trace heap resizes.
.TP
\fIheap-shot\fR, \fIheap\fR or \fIh\fR
-Performsn full heap profiling. In this case on each
+Performs full heap profiling. In this case on each
collection a full heap snapshot is recorded to disk.
+Inside the snapshots, each object reference is still represented so
+that it's possible to investigate who is responsible for keeping objects
+alive.
+.PP
+The actual production of heap snapshots could produce large log files,
+so it can be controlled in three ways:
+.TP
+\fIgc-dumps=N\fR, \fIgc-d=N\fR, \fIgcd=N\fR
+states the number of snapshots that must be dumped (since the application
+starts). Zero means no dumps at all, -1 means dump at all collections.
+.TP
+\fIgc-signal=<signal>\fR, \fIgc-s\fR or \fIgcs\fR
+(where <signal> is one of "SIGUSR1", "SIGUSR2", or "SIGPROF")
+specifies a signal that will immediately trigger a collection and a dump.
.TP
\fIgc-commands=FILE\fR, \fIgc-c=FILE\fR or \fIgcc=FILE\fR
-Used to specify the file that controls the heap snapshot dumps.
+specify a "command file". The file must contain an integer value in ASCII
+form, and the profiler will stat it at every collection.
+If it has been modified it will interpret its contents as a \fIgcd=N\fR
+option value, and dump the required number of snapshots from that moment
+onwards.
+If the file is present at application startup it takes precedence over an
+eventual \fIgcd=N\fR option.
+.ne
+.RE
+.PP
+\fBProfiler activity control\fR
+.RS
+.ne 8
.TP
-\fIgc-dumps=N\fR, \fIgc-d=N\fR, \fIgcd=N\fR
-Used to specify the initial number of heap snapshots to dump (if the control file is not used).
+\fIoutput=FILE\fR, \fIout=FILE\fR or \fIo=FILE\fR
+Use this option to provide the output file name for the profile log.
+If this option is not specified, it will default to "<program-name>.mprof".
+.TP
+\fIoutput-suffix=SUFFIX\fR, \fIsuffix=SUFFIX\fR or \fIos=SUFFIX\fR: makes
+the output file name equals to "<program-name>-SUFFIX.mprof".
+.TP
+\fIstart-enabled\fR or \fIse\fR: start with the profiler active
+(which is the default).
+.TP
+\fIstart-disabled\fR or \fIsd\fR: start with the profiler inactive.
+.TP
+\fItoggle-signal=<SIGNAL>\fR or \fIts=<SIGNAL>\fR (where <SIGNAL>
+is one of SIGUSR1, SIGUSR2 or SIGPROF): Choose a signal that will be used to
+toggle the profiler activity on and off. This way you can decide to profile
+only portions of the applicatopn lifetime (for instance, you can decide to
+avoid profiling an initial setup phase using \fIsd\fR, and enable the
+profiler later delivering the signal to the application).
+.TP
+\fIforce-accurate-timer\fR (or \fIfac\fR): the profiler by default uses
+rtdsc to acquire timestamps for frequent events, but this can be imprecise;
+using this option you force the use of "gettimeofday" at every event, which
+is more accurate but much slower.
+.ne
+.RE
+.PP
+\fBInternal buffer sizes\fR
+.RS
+.ne 8
.TP
\fIper-thread-buffer-size=N\fR, \fItbs=N\fR
Use to specify the number of events that a thread buffer
-can hold. When the thread buffer is full, the log block it is
+can hold. When the thread buffer is full, a log block is
written to disk.
.Sp
This defaults to tbs=10000.
The number of statistical samples that
are held in memory before they are dumped to disk (the system does
double-buffering and the statistical samples are written by a helper
-thread).
+thread, so the statistical profiler never stops and is able to profile
+the profiler itself).
.Sp
This defaults to sbs=10000.
.TP
.ne
.RE
.PP
-A few invocation samples follow.
-.PP
-To collect statistical data:
-.nf
-
- mono --profile=logging:s program.exe
-.fi
-.PP
-To profile method enter-exit and allocations:
-.nf
-
- mono --profile=logging:c,a program.exe
-.fi
-.PP
-To profile method enter-exit and jit time, and write the data to "mydata.mprof":
-.nf
-
- mono --profile=logging:c,j,o=mydata.mprof program.exe
-.fi
-.PP
-Then you would need to invoke the decoder on "mydata.mprof" to see the
-profiling results.
-.PP
In its current state, this profiler can also perform heap analysis (like
heap-shot), and the decoder is already able to read the data, however
-the user interface for this feature has not yet been written (which means
-that the data is not printed by the decoder).
+the user interface for this feature is experimental (the
+\fImprof-heap-viewer\fR tool in the mono-tools module).
+.PP
+Another known issue is that if the timer is not strictly monotonic (like
+rtdsc), differences between times can underflow (they are handled as
+unsigned integers) and weird numbers can show up in the logs.
+.PP
+Finally, it can happen that when exceptions are thrown the profiler temporarily
+loses track of the execution stack and misattributes the caller for a few
+allocations (and method execution time).
.PP
More explanations are provided here: "http://www.mono-project.com/LoggingProfiler".
.SH EXTERNAL PROFILERS
To install you must download the profiler
from Mono's SVN:
.nf
- svn co svn://svn.myrealbox.com/source/trunk/heap-shot
+ svn co svn://anonsvn.mono-project.com/source/trunk/heap-shot
cd heap-shot
./autogen
make
objects of a given type. To install you must download the profiler
from Mono's SVN:
.nf
- svn co svn://svn.myrealbox.com/source/trunk/heap-prof
+ svn co svn://anonsvn.mono-project.com/source/trunk/heap-prof
cd heap-prof
./autogen
make
.PP
A more powerful coverage tool is available in the module `monocov'.
See the monocov(1) man page for details.
-.SH DEBUGGING
+.SH DEBUGGING AIDS
+To debug managed applications, you can use the
+.B mdb
+command, a command line debugger.
+.PP
It is possible to obtain a stack trace of all the active threads in
Mono by sending the QUIT signal to Mono, you can do this from the
command line, like this:
and the application might crash or terminate at any given point
afterwards.
.PP
+The \fB--debug=casts\FR option can be used to get more detailed
+information for Invalid Cast operations, it will provide information
+about the types involved.
+.PP
You can use the MONO_LOG_LEVEL and MONO_LOG_MASK environment variables
to get verbose debugging output about the execution of your
application within Mono.
\fBno-gdb-backtrace\fR
This option will disable the GDB backtrace emitted by the runtime
after a SIGSEGV or SIGABRT in unmanaged code.
+.TP
+\fBsuspend-on-sigsegv\fR
+
+This option will suspend the program when a native SIGSEGV is received.
+This is useful for debugging crashes which do not happen under gdb,
+since a live process contains more information than a core file.
.ne
.RE
.TP
\fBMONO_THREADS_PER_CPU\fR
The maximum number of threads in the general threadpool will be
20 + (MONO_THREADS_PER_CPU * number of CPUs). The default value for this
-variable is 5.
+variable is 10.
.TP
\fBMONO_XMLSERIALIZER_THS\fR
Controls the threshold for the XmlSerializer to produce a custom
makes it hard to isolate the root of certain problems.
.TP
\fBMONO_GENERIC_SHARING\fR
-This environment variable is completely unsupported, don't use it.
-This controls for which classes to enable generic code sharing in
-principle. Permissible values are "all", "corlib" and "none". The
-default is "corlib", meaning that sharing can only happen for corlib
-classes. Note that to enable generation of shared code the "gshared"
-compiler option has to be set as well.
+This environment variable controls the kind of generic sharing used.
+This variable is used by internal JIT developers and should not be
+changed in production. Do not use it.
+.Sp
+The variable controls which classes will have generic code sharing
+enabled.
+.Sp
+Permissible values are:
+.RS
+.TP
+.I "all"
+All generated code can be shared.
+.TP
+.I "collections"
+Only the classes in System.Collections.Generic will have its code
+shared (this is the default value).
+.TP
+.I "corlib"
+Only code in corlib will have its code shared.
+.TP
+.I "none"
+No generic code sharing will be performed.
+.RE
+.Sp
+Generic code sharing by default only applies to collections. The
+Mono JIT by default turns this on.
+.TP
+\fBMONO_XDEBUG\fR
+When the the MONO_XDEBUG env var is set, debugging info for JITted
+code is emitted into a shared library, loadable into gdb. This enables,
+for example, to see managed frame names on gdb backtraces.
+.TP
+\fBMONO_VERBOSE_METHOD\fR
+Enables the maximum JIT verbosity for the specified method. This is
+very helpfull to diagnose a miscompilation problems of a specific
+method.
.SH VALGRIND
If you want to use Valgrind, you will find the file `mono.supp'
useful, it contains the suppressions for the GC which trigger
http://www.mono-project.com
.SH SEE ALSO
.PP
-certmgr(1), mcs(1), monocov(1), monodis(1), mono-config(5), mozroots(1), xsp(1).
+certmgr(1), csharp(1), mcs(1), mdb(1), monocov(1), monodis(1), mono-config(5), mozroots(1), xsp(1).
.PP
For more information on AOT:
http://www.mono-project.com/AOT
projects / mono.git / blobdiff