jk2addict has asked for the wisdom of the Perl Monks concerning the following question:
This all started with a report from a user about Class::Accessor::Grouped being much slower on 5.10 compared to 5.8.8.
At this point, I call 'not it'...but only because I really don't know what in the hell is going on. Two brand new fresh FreeBSD 6.2 installs. One with a a compiled (not ports) Perl 5.8.8 and the other with a compiled 5.10.0.
The test case is simple set_inherited, sans C::A::G in the picture, since the reporter noted set was slower as well (which BTW has no MRO interaction):
#test.pl use lib '.'; use Foo; use Benchmark ':all'; my $f = bless {}, 'Foo'; timethese(0, { set_inherited_class => sub {Foo->set_inherited('bar', 'baz')}, set_inherited_object => sub {$f->set_inherited('bar', 'baz')} }); ##Foo.pm package Foo; use Scalar::Util qw/blessed reftype/; sub set_inherited { my ($self, $set, $val) = @_; if (blessed $self) { if (reftype $self eq 'HASH') { return $self->{$set} = $val; } else { croak('Cannot set inherited value on an object instance th +at is not hash-based'); }; } else { no strict 'refs'; return ${$self.'::__cag_'.$set} = $val; }; } 1;
The results are:
Perl 5.8.8 Machine: > Benchmark: running set_inherited_class, set_inherited_object for at +least 3 CPU seconds... > set_inherited_class: 4 wallclock secs ( 3.16 usr + 0.00 sys = 3.1 +6 CPU) @ 575596.40/s (n=1821223) > set_inherited_object: 3 wallclock secs ( 3.16 usr + -0.01 sys = 3. +15 CPU) @ 687794.82/s (n=2165479) > claco@fbsd588 ~ $ Perl 5.10.0 Machine: > Benchmark: running set_inherited_class, set_inherited_object for at +least 3 CPU seconds... > set_inherited_class: 3 wallclock secs ( 3.12 usr + 0.01 sys = 3.1 +3 CPU) @ 335388.09/s (n=1050708) > set_inherited_object: 2 wallclock secs ( 3.15 usr + 0.00 sys = 3. +15 CPU) @ 412676.76/s (n=1299287) > claco@fbsd510 ~ $
My to my shock, if I whittle down the code in set_inherited to just this:
package Foo; use Scalar::Util qw/blessed reftype/; sub set_inherited { my ($self, $set, $val) = @_; } 1;
performance still seriouesly sucks:
5.8.8 > Benchmark: running set_inherited_class, set_inherited_object for at +least 3 CPU seconds... > set_inherited_class: 3 wallclock secs ( 3.08 usr + 0.02 sys = 3.0 +9 CPU) @ 1199923.07/s (n=3712262) > set_inherited_object: 4 wallclock secs ( 3.27 usr + 0.00 sys = 3. +27 CPU) @ 1380589.06/s (n=4519272) > claco@fbsd588 ~ $ 5.10.0 > Benchmark: running set_inherited_class, set_inherited_object for at +least 3 CPU seconds... > set_inherited_class: 4 wallclock secs ( 3.09 usr + 0.01 sys = 3.1 +0 CPU) @ 536733.34/s (n=1664712) > set_inherited_object: 4 wallclock secs ( 3.13 usr + 0.00 sys = 3. +13 CPU) @ 638055.42/s (n=1998908) > claco@fbsd510 ~ $
A this point, I'm stumped. my ($, $, $) = @_; is a common idiom. Changing to this makes 5.10 faster.
package Foo; use Scalar::Util qw/blessed reftype/; sub set_inherited { my $self = shift; my $set = shift; my $val = shift; } 1;
I know shift is always faster than assigning @_, but the performaance difference of assigning @_ on 5.10 vs. 5.8.8 is worrysome to me.
Updated with -V output
Summary of my perl5 (revision 5 version 8 subversion 8) configuration: Platform: osname=freebsd, osvers=6.2-release, archname=i386-freebsd uname='freebsd fbsd588.local 6.2-release freebsd 6.2-release #0: f +ri jan 12 10:40:27 utc 2007 root@dessler.cse.buffalo.edu:usrobjusrsrc +sysgeneric i386 ' config_args='-de' 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=undef use64bitall=undef uselongdouble=undef usemymalloc=n, bincompat5005=undef Compiler: cc='cc', ccflags ='-DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-stri +ct-aliasing -pipe -Wdeclaration-after-statement -I/usr/local/include' +, optimize='-O', cppflags='-DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasi +ng -pipe -Wdeclaration-after-statement -I/usr/local/include' ccversion='', gccversion='3.4.6 [FreeBSD] 20060305', gccosandvers= +'' intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1 +2 ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', + lseeksize=8 alignbytes=4, prototype=define Linker and Libraries: ld='cc', ldflags ='-Wl,-E -L/usr/local/lib' libpth=/usr/lib /usr/local/lib libs=-lm -lcrypt -lutil -lc perllibs=-lm -lcrypt -lutil -lc libc=, so=so, useshrplib=false, libperl=libperl.a gnulibc_version='' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' ' cccdlflags='-DPIC -fPIC', lddlflags='-shared -L/usr/local/lib' Characteristics of this binary (from libperl): Compile-time options: PERL_MALLOC_WRAP USE_LARGE_FILES USE_PERLIO Built under freebsd Compiled at Dec 22 2007 15:52:43 @INC: /usr/local/lib/perl5/5.8.8/i386-freebsd /usr/local/lib/perl5/5.8.8 /usr/local/lib/perl5/site_perl/5.8.8/i386-freebsd /usr/local/lib/perl5/site_perl/5.8.8 /usr/local/lib/perl5/site_perl . ------------- Summary of my perl5 (revision 5 version 10 subversion 0) configuration +: Platform: osname=freebsd, osvers=6.2-release, archname=i386-freebsd uname='freebsd fbsd510.local 6.2-release freebsd 6.2-release #0: f +ri jan 12 10:40:27 utc 2007 root@dessler.cse.buffalo.edu:usrobjusrsrc +sysgeneric i386 ' config_args='' hint=recommended, useposix=true, d_sigaction=define useithreads=undef, usemultiplicity=undef useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=und +ef use64bitint=undef, use64bitall=undef, uselongdouble=undef usemymalloc=n, bincompat5005=undef Compiler: cc='cc', ccflags ='-DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-stri +ct-aliasing -pipe -I/usr/local/include', optimize='-O', cppflags='-DHAS_FPSETMASK -DHAS_FLOATINGPOINT_H -fno-strict-aliasi +ng -pipe -I/usr/local/include' ccversion='', gccversion='3.4.6 [FreeBSD] 20060305', gccosandvers= +'' intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1 +2 ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', + lseeksize=8 alignbytes=4, prototype=define Linker and Libraries: ld='cc', ldflags ='-Wl,-E -L/usr/local/lib' libpth=/usr/lib /usr/local/lib libs=-lm -lcrypt -lutil -lc perllibs=-lm -lcrypt -lutil -lc libc=, so=so, useshrplib=false, libperl=libperl.a gnulibc_version='' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags=' ' cccdlflags='-DPIC -fPIC', lddlflags='-shared -L/usr/local/lib' Characteristics of this binary (from libperl): Compile-time options: PERL_DONT_CREATE_GVSV PERL_MALLOC_WRAP USE_LARGE_FILES USE_PERLIO Built under freebsd Compiled at Dec 22 2007 17:32:47 @INC: /usr/local/lib/perl5/5.10.0/i386-freebsd /usr/local/lib/perl5/5.10.0 /usr/local/lib/perl5/site_perl/5.10.0/i386-freebsd /usr/local/lib/perl5/site_perl/5.10.0 .
Updated: Also this from a thread on use.perl. I hate cross posting, but given the nature of this issue...
Back to
Seekers of Perl Wisdom