On 4/27/15 11:25 AM, Alexandre DERUMIER wrote: >>> Looks like the default is 16MB: >>> http://gperftools.googlecode.com/svn/trunk/doc/tcmalloc.html > > I don't known if setting it to 128MB have performance impact (cpu, memory > garbage collection ?) > I'll try to test different values between 16->128MB.
It looks like the mongodb people have run into a similar issue in a particular (degenerate) case. Here's the ticket link for reference: https://jira.mongodb.org/browse/SERVER-16551 > > > > > ----- Mail original ----- > De: "Mark Nelson" <[email protected]> > À: "Milosz Tanski" <[email protected]>, "aderumier" <[email protected]>, > "ceph-devel" <[email protected]>, "Somnath Roy" > <[email protected]> > Envoyé: Lundi 27 Avril 2015 16:57:44 > Objet: Re: Hitting tcmalloc bug even with patch applied > > Looks like the default is 16MB: > > http://gperftools.googlecode.com/svn/trunk/doc/tcmalloc.html > > On 04/27/2015 09:53 AM, Milosz Tanski wrote: >> >> >> On 4/27/15 9:21 AM, Alexandre DERUMIER wrote: >>> Seem that starting osd with: >>> >>> TCMALLOC_MAX_TOTAL_THREAD_CACHE_BYTES=128M /usr/bin/ceph-osd >>> >>> fix it. >>> >>> I don't known if it's the right way ? >> >> Do you know what the default is if you don't specify it? >>> >>> >>> >>> ----- Mail original ----- >>> De: "aderumier" <[email protected]> >>> À: "ceph-devel" <[email protected]>, "Somnath Roy" >>> <[email protected]> >>> Envoyé: Lundi 27 Avril 2015 14:06:22 >>> Objet: Hitting tcmalloc bug even with patch applied >>> >>> Hi, >>> >>> I'm hitting the tcmalloc even with patch apply. >>> It's mainly occur when I try to bench fio with a lot jobs (20 - 40 jobs) >>> >>> Does It need to tuned something in osd environnement variable ? >>> >>> >>> I double check it with >>> >>> #g++ -o gperftest gperftest.c -ltcmalloc >>> # export TCMALLOC_MAX_TOTAL_THREAD_CACHE_BYTES=67108864 >>> # ./gperftest >>> Tcmalloc OK! Internal and Env cache size are same:67108864 >>> >>> >>> perf top >>> ------- >>> 10.04% libtcmalloc.so.4.1.2 [.] >>> tcmalloc::ThreadCache::ReleaseToCentralCache >>> 8.19% libtcmalloc.so.4.1.2 [.] tcmalloc::CentralFreeList::FetchFromSpans >>> 3.89% libtcmalloc.so.4.1.2 [.] tcmalloc::CentralFreeList::ReleaseToSpans >>> 2.04% libtcmalloc.so.4.1.2 [.] >>> tcmalloc::CentralFreeList::ReleaseListToSpans >>> 1.79% libtcmalloc.so.4.1.2 [.] operator new >>> 1.25% ceph-osd [.] ConfFile::load_from_buffer >>> 1.21% libtcmalloc.so.4.1.2 [.] operator delete >>> 1.14% [kernel] [k] _raw_spin_lock >>> 1.08% libstdc++.so.6.0.19 [.] std::basic_string<char, >>> std::char_traits<char>, std::allocator<char> >::basic_string >>> 1.04% [kernel] [k] __schedule >>> 1.00% libpthread-2.17.so [.] pthread_mutex_trylock >>> 0.90% [kernel] [k] native_write_msr_safe >>> 0.89% [kernel] [k] __switch_to >>> 0.79% [kernel] [k] _raw_spin_lock_irqsave >>> 0.73% [kernel] [k] copy_user_enhanced_fast_string >>> >>> >>> >>> Regards, >>> >>> Alexandre >> >> -- >> To unsubscribe from this list: send the line "unsubscribe ceph-devel" in >> the body of a message to [email protected] >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
