| Subject: | Memory Leak |
Distribution: XML-LibXML-1.58
LibXML version : 2.6.16
Summary
When perl destroys a document created with the XML::LibXML parse_string method, it leaks ~88 bytes of memory.
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Test Box #1
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[jobs@dev fix]$ uname -a
Linux dev 2.4.21-4.EL #1 Fri Oct 3 18:13:58 EDT 2003 i686 i686 i386 GNU/Linux
[jobs@dev fix]$ perl -V
Summary of my perl5 (revision 5.0 version 8 subversion 0) configuration:
Platform:
osname=linux, osvers=2.4.21-1.1931.2.393.entsmp, archname=i386-linux-thread-multi
uname='linux por'
config_args='-des -Doptimize=-O2 -g -pipe -march=i386 -mcpu=i686 -Dmyhostname=localhost -Dperladmin=root@localhost -Dcc=gcc -Dcf_by=Red Hat, Inc. -Dinstallprefix=/usr -Dprefix=/usr -Darchname=i386-linux -Dvendorprefix=/usr -Dsiteprefix=/usr -Dotherlibdirs=/usr/lib/perl5/5.8.0 -Duseshrplib -Dusethreads -Duseithreads -Duselargefiles -Dd_dosuid -Dd_semctl_semun -Di_db -Ui_ndbm -Di_gdbm -Di_shadow -Di_syslog -Dman3ext=3pm -Duseperlio -Dinstallusrbinperl -Ubincompat5005 -Uversiononly -Dpager=/usr/bin/less -isr'
hint=recommended, useposix=true, d_sigaction=define
usethreads=define use5005threads=undef'
useithreads=define usemultiplicity=
useperlio= d_sfio=undef uselargefiles=define usesocks=undef
use64bitint=undef use64bitall=un uselongdouble=
usemymalloc=, bincompat5005=undef
Compiler:
cc='gcc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBUGGING -fno-strict-aliasing -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm',
optimize='',
cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBUGGING -fno-strict-aliasing -I/usr/local/include -I/usr/include/gdbm'
ccversion='', gccversion='3.2.3 20030502 (Red Hat Linux 3.2.3-19)', gccosandvers=''
gccversion='3.2.3 200305'
intsize=o, longsize=s, ptrsize=l, doublesize=8, byteorder=1234
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
ivtype='long'
k', ivsize=4'
ivtype, nvtype='double'
o_no', nvsize=, Off_t='', lseeksize=8
alignbytes=4, prototype=define
Linker and Libraries:
ld='gcc'
l', ldflags =' -L/usr/local/lib'
ldflags_use'
libpth=/usr/local/lib /lib /usr/lib
libs=-lnsl -lgdbm -ldb -ldl -lm -lpthread -lc -lcrypt -lutil
perllibs=
libc=/lib/libc-2.3.2.so, so=so, useshrplib=true, libperl=libper
gnulibc_version='2.3.2'
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so', d_dlsymun=undef, ccdlflags='-rdynamic -Wl,-rpath,/usr/lib/perl5/5.8.0/i386-linux-thread-multi/CORE'
cccdlflags='-fPIC'
ccdlflags='-rdynamic -Wl,-rpath,/usr/lib/perl5', lddlflags='s Unicode/Normalize XS/A'
Characteristics of this binary (from libperl):
Compile-time options: DEBUGGING MULTIPLICITY USE_ITHREADS USE_LARGE_FILES PERL_IMPLICIT_CONTEXT
Locally applied patches:
MAINT18379
Built under linux
Compiled at Sep 15 2003 10:03:52
@INC:
/usr/lib/perl5/5.8.0/i386-linux-thread-multi
/usr/lib/perl5/5.8.0
/usr/lib/perl5/site_perl/5.8.0/i386-linux-thread-multi
/usr/lib/perl5/site_perl/5.8.0
/usr/lib/perl5/site_perl
/usr/lib/perl5/vendor_perl/5.8.0/i386-linux-thread-multi
/usr/lib/perl5/vendor_perl/5.8.0
/usr/lib/perl5/vendor_perl
/usr/lib/perl5/5.8.0/i386-linux-thread-multi
/usr/lib/perl5/5.8.0
.
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Test Box #2
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[jobs@rock jobs]$ uname -a
Linux rock 2.4.21-15.ELsmp #1 SMP Thu Apr 22 00:18:24 EDT 2004 i686 i686 i386 GNU/Linux
[jobs@rock jobs]$ perl -V
Summary of my perl5 (revision 5 version 8 subversion 5) configuration:
Platform:
osname=linux, osvers=2.4.21-15.elsmp, archname=i686-linux
uname='linux rock.knobias.com 2.4.21-15.elsmp #1 smp thu apr 22 00:18:24 edt 2004 i686 i686 i386 gnulinux '
config_args='-de'
hint=recommended, useposix=true, d_sigaction=define
usethreads=undef use5005threads=undef useithreads=undef usemultiplicity=undef
useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
use64bitint=undef use64bitall=undef uselongdouble=undef
usemymalloc=n, bincompat5005=undef
Compiler:
cc='cc', ccflags ='-fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm',
optimize='-O2',
cppflags='-fno-strict-aliasing -pipe -I/usr/local/include -I/usr/include/gdbm'
ccversion='', gccversion='3.2.3 20030502 (Red Hat Linux 3.2.3-34)', gccosandvers=''
intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
alignbytes=4, prototype=define
Linker and Libraries:
ld='cc', ldflags =' -L/usr/local/lib'
libpth=/usr/local/lib /lib /usr/lib
libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc
perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc
libc=/lib/libc-2.3.2.so, so=so, useshrplib=false, libperl=libperl.a
gnulibc_version='2.3.2'
Dynamic Linking:
dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
cccdlflags='-fpic', lddlflags='-shared -L/usr/local/lib'
Characteristics of this binary (from libperl):
Compile-time options: USE_LARGE_FILES
Built under linux
Compiled at Oct 19 2004 16:05:49
@INC:
/usr/local/lib/perl5/5.8.5/i686-linux
/usr/local/lib/perl5/5.8.5
/usr/local/lib/perl5/site_perl/5.8.5/i686-linux
/usr/local/lib/perl5/site_perl/5.8.5
/usr/local/lib/perl5/site_perl
.
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How to Reproduce
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file leak.pl
#!/usr/bin/perl
$| = 1;
use strict;
use XML::LibXML;
my $xml = sprintf <<EOD;
<?xml version="1.0"?>
<blah>
<blarg>this is blarg.</blarg>
<blarf>this is blarf.</blarf>
</blah>
EOD
my $parser = XML::LibXML->new();
for (my $x = 0; $x < 1000000; $x++) {
my $doc = $parser->parse_string($xml);
if ($x % 1000 == 0) {
print "checkpoint $x\n";
}
if ($x % 10000 == 0) {
print " sleeping for 10\n";
sleep 10;
}
}
Start up 2 shells into the same box. In one, run top. In the other, run the script from above. Filter top down to make the test script visible, and watch the process memory grow out of control.