Is the profiled Perl app actually using substantial proportions of those memory figures?

Hi

The perl code is not using much memory, but there is a lot of block evals and creating objects with lots of DateTime timestamps (DateTime has a horrendously large structure regarding the timezone).

I'm in the process of making a narrowed down profiling only doing the perl part.

My thought was that if you were random accessing a substantial part of those memories, 64 GB via 8MB secondary cache would lead to higher cache contention that 40GB via 8MB. But unless both boxes are running close to their upper limits--not just your Perl jobs; but their full workloads--that's unlikely to be the cause.

The only other thought that comes to mind is that one machine is using (say) the pure-Perl version of something like List::Util and the other the XS version. I rememeber one install on my old machine where the XS version appeared to be installed--the proper files were in thr right places--but it was silently using the PP version anyway. I never fully understood the cause, but a forces re-install fixed it.

---

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Its the full 64bit

[root@lxwscpapp4 ~]# cat /etc/redhat-release
Red Hat Enterprise Linux AS release 4 (Nahant Update 7)
[root@lxwscpapp4 ~]# uname -a
Linux lxwscpapp4 2.6.9-78.0.22.ELlargesmp #1 SMP Fri Apr 24 12:59:13 E
+DT 2009 x86_64 x86_64 x86_64 GNU/Linux
[root@lxwscpapp4 ~]# cat /proc/meminfo
MemTotal:     65986620 kB
MemFree:      49984384 kB
Buffers:        251780 kB
Cached:       15235444 kB
SwapCached:          0 kB
Active:       15455460 kB
Inactive:       243860 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:     65986620 kB
LowFree:      49984384 kB
SwapTotal:     1048568 kB
SwapFree:      1048568 kB
Dirty:              36 kB
Writeback:           0 kB
Mapped:         265268 kB
Slab:           267256 kB
CommitLimit:  34041876 kB
Committed_AS:  1783772 kB
PageTables:       4816 kB
VmallocTotal: 536870911 kB

[root@lxwscpapp4 ~]# /opt/perl/bin/perl -V
Summary of my perl5 (revision 5 version 8 subversion 9) configuration:
  Platform:
    osname=linux, osvers=2.6.9-78.0.22.ellargesmp, archname=x86_64-lin
+ux
    uname='linux lxwscpapp4 2.6.9-78.0.22.ellargesmp #1 smp fri apr 24
+ 12:59:13 edt 2009 x86_64 x86_64 x86_64 gnulinux '
    config_args='-Dprefix=/opt/perl -Dnoextensions=ODBM_File -des -Acc
+flags=-fPIC'
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=undef use5005threads=undef useithreads=undef usemultipl
+icity=undef
    useperlio=define d_sfio=undef uselargefiles=define usesocks=undef
    use64bitint=define use64bitall=define uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-fPIC -fno-strict-aliasing -pipe -I/usr/local/i
+nclude -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2',
    cppflags='-fPIC -fno-strict-aliasing -pipe -I/usr/local/include'
    ccversion='', gccversion='3.4.6 20060404 (Red Hat 3.4.6-10)', gcco
+sandvers=''
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1
+6
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
+ lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib /lib64 /usr/lib64 /usr/local/l
+ib64
    libs=-lnsl -ldl -lm -lcrypt -lutil -lc
    perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc
    libc=/lib/libc-2.3.4.so, so=so, useshrplib=false, libperl=libperl.
+a
    gnulibc_version='2.3.4'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -L/usr/local/lib'


Characteristics of this binary (from libperl):
  Compile-time options: PERL_MALLOC_WRAP USE_64_BIT_ALL USE_64_BIT_INT
                        USE_FAST_STDIO USE_LARGE_FILES USE_PERLIO
  Built under linux
  Compiled at Nov 16 2009 09:21:45
  @INC:
    /opt/perl/lib/5.8.9/x86_64-linux
    /opt/perl/lib/5.8.9
    /opt/perl/lib/site_perl/5.8.9/x86_64-linux
    /opt/perl/lib/site_perl/5.8.9
    .

VmallocUsed:      4356 kB
VmallocChunk: 536866351 kB
HugePages_Total:     0
HugePages_Free:      0
Hugepagesize:     2048 kB
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