DOKK / manpages / debian 12 / libdevel-mat-perl / Devel::MAT.3pm.en
Devel::MAT(3pm) User Contributed Perl Documentation Devel::MAT(3pm)

"Devel::MAT" - Perl Memory Analysis Tool

NEW USERS:

If you are new to the "Devel::MAT" set of tools, this is probably not the document you want to start with. If you are interested in using "Devel::MAT" to help diagnose memory-related problems in a perl program you instead want to read the user guide, at Devel::MAT::UserGuide.

If you are writing tooling modules to extend the abilities of "Devel::MAT" then this may indeed by the document for you; read on...

A "Devel::MAT" instance loads a heapdump file, and provides a container to store analysis tools to work on it. Tools may be provided that conform to the Devel::MAT::Tool API, which can help analyse the data and interact with the explorer user interface by using the methods in the Devel::MAT::UI package.

The dump file format is still under development, so at present no guarantees are made on whether files can be loaded over mismatching versions of "Devel::MAT". However, as of version 0.11 the format should be more extensible, allowing new SV fields to be added without breaking loading - older tools will ignore new fields and newer tools will just load undef for fields absent in older files. As the distribution approaches maturity the format will be made more stable.

   $pmat = Devel::MAT->load( $path, %args )

Loads a heap dump file from the given path, and returns a new "Devel::MAT" instance wrapping it.

   $df = $pmat->dumpfile

Returns the underlying Devel::MAT::Dumpfile instance backing this analysis object.

   @tools = $pmat->available_tools

Lists the Devel::MAT::Tool classes that are installed and available.

   $tool = $pmat->load_tool( $name )

Loads the named Devel::MAT::Tool class.

   $bool = $pmat->has_tool( $name )

Returns true if the named tool is already loaded.

   $pmat->run_command( $inv )

Runs a tool command given by the Commandable::Invocation instance.

   $node = $pmat->inref_graph( $sv, %opts )

Traces the tree of inrefs from $sv back towards the known roots, returning a Devel::MAT::Graph node object representing it, within a graph of reverse references back to the known roots.

This method will load Devel::MAT::Tool::Inrefs if it isn't yet loaded.

The following named options are recognised:

If specified, stop recursing after the specified count. A depth of 1 will only include immediately referring SVs, 2 will print the referrers of those, etc. Nodes with inrefs that were trimmed because of this limit will appear to be roots with a special name of "EDEPTH".
Specifies the type of inrefs followed. By default all inrefs are followed. Passing "strong" will follow only strong direct inrefs. Passing "direct" will follow only direct inrefs.
If true, attempt to neaten up the output by skipping over certain structures.

"REF()"-type SVs will be skipped to their referrant.

Members of the symbol table will be printed as being a 'root' element of the given symbol name.

"PAD"s and "PADLIST"s will be skipped to their referring "CODE", giving shorter output for lexical variables.

   $sv = $pmat->find_symbol( $name )

Attempts to walk the symbol table looking for a symbol of the given name, which must include the sigil.

   $Package::Name::symbol_name => to return a SCALAR SV
   @Package::Name::symbol_name => to return an ARRAY SV
   %Package::Name::symbol_name => to return a HASH SV
   &Package::Name::symbol_name => to return a CODE SV

   $gv = $pmat->find_glob( $name )

Attempts to walk the symbol table looking for a symbol of the given name, returning the "GLOB" object if found.

   $stash = $pmat->find_stash( $name )

Attempts to walk the symbol table looking for a stash of the given name.

Paul Evans <leonerd@leonerd.org.uk>

2023-03-26 perl v5.36.0