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NAME

Devel::MAT::Dumpfile - load and analyse a heap dump file

SYNOPSIS

use Devel::MAT::Dumpfile;

my $df = Devel::MAT::Dumpfile->load( "path/to/the/file.pmat" );

DESCRIPTION

This module provides a class that loads a heap dump file previously written by Devel::MAT::Dumper. It provides accessor methods to obtain various well-known root starting addresses, or to find arbitrary SVs by address. Each SV is represented by an instance of Devel::MAT::SV.

CONSTRUCTOR

load

$df = Devel::MAT::Dumpfile->load( $path, %args );

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

Takes the following named arguments:

progress => CODE

If given, should be a CODE reference to a function that will be called regularly during the loading process, and given a status message to update the user.

METHODS

perlversion

$version = $df->perlversion;

Returns the version of perl that the heap dump file was created by, as a string in the form 5.14.2.

endian

$endian = $df->endian;

Returns the endian direction of the perl that the heap dump was created by, as either big or little.

uint_len

$len = $df->uint_len;

Returns the length in bytes of a uint field of the perl that the heap dump was created by.

ptr_len

$len = $df->ptr_len;

Returns the length in bytes of a pointer field of the perl that the heap dump was created by.

nv_len

$len = $df->nv_len;

Returns the length in bytes of a double field of the perl that the heap dump was created by.

ithreads

$ithreads = $df->ithreads;

Returns a boolean indicating whether ithread support was enabled in the perl that the heap dump was created by.

roots

%roots = $df->roots;

Returns a key/value pair list giving the names and SVs at each of the roots.

roots_strong

%roots = $df->roots_strong;

Returns a key/value pair list giving the names and SVs at each of the roots that count as strong references.

roots_weak

%roots = $df->roots_weak;

Returns a key/value pair list giving the names and SVs at each of the roots that count as strong references.

ROOTS

$sv = $df->ROOT;

For each of the root names given below, a method exists with that name which returns the SV at that root:

main_cv
defstash
mainstack
beginav
checkav
unitcheckav
initav
endav
strtabhv
envgv
incgv
statgv
statname
tmpsv
defgv
argvgv
argvoutgv
argvout_stack
fdpidav
preambleav
modglobalhv
regex_padav
sortstash
firstgv
secondgv
debstash
stashcache
isarev
registered_mros

root_descriptions

%rootdescs = $df->root_descriptions;

Returns a key/value pair list giving the (method) name and description text of each of the possible roots.

root_at

$addr = $df->root_at( $name );

Returns the SV address of the given named root.

root

$sv = $df->root( $name );

Returns the given root SV.

heap

@svs = $df->heap;

Returns all of the heap-allocated SVs, in no particular order

stack

@svs = $df->stack;

Returns all the SVs on the stack

contexts

@ctxs = $df->contexts;

Returns a list of Devel::MAT::Context objects representing the call context stack in the dumpfile.

sv_at

$sv = $df->sv_at( $addr );

Returns the SV at the given address, or undef if one does not exist.

(Note that this is unambiguous, as a Perl-level undef is represented by the immortal Devel::MAT::SV::UNDEF SV).

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>