Hey Mark and list, FYI for you and the list: Samuel and I seem to have found and fixed the remaining performance-problems. For those who can't wait, fixes are in "wip-dumpling-perf2" and will probably be in the next point-release. Regards, Oliver On 27-08-13 17:13, Mark Nelson wrote: > Ok, definitely let us know how it goes! For what it's worth, I'm > testing Sam's wip-dumpling-perf branch with the wbthrottle code disabled > now and comparing it both to that same branch with it enabled along with > 0.67.1. Don't have any perf data, but quite a bit of other data to look > through, both in terms of RADOS bench and RBD. > > Mark > > On 08/27/2013 10:07 AM, Oliver Daudey wrote: >> Hey Mark, >> >> That will take a day or so for me to know with enough certainty. With >> the low CPU-usage and preliminary results today, I'm confident enough to >> upgrade all OSDs in production and test the cluster all-Dumpling >> tomorrow. For now, I only upgraded a single OSD and measured CPU-usage >> and whatever performance-effects that had on the cluster, so if I would >> lose that OSD, I could recover. :-) Will get back to you. >> >> >> Regards, >> >> Oliver >> >> On 27-08-13 15:04, Mark Nelson wrote: >>> Hi Olver/Matthew, >>> >>> Ignoring CPU usage, has speed remained slower as well? >>> >>> Mark >>> >>> On 08/27/2013 03:08 AM, Oliver Daudey wrote: >>>> Hey Samuel, >>>> >>>> The "PGLog::check()" is now no longer visible in profiling, so it >>>> helped >>>> for that. Unfortunately, it doesn't seem to have helped to bring down >>>> the OSD's CPU-loading much. Leveldb still uses much more than in >>>> Cuttlefish. On my test-cluster, I didn't notice any difference in the >>>> RBD bench-results, either, so I have to assume that it didn't help >>>> performance much. >>>> >>>> Here's the `perf top' I took just now on my production-cluster with >>>> your >>>> new version, under regular load. Also note the "memcmp" and "memcpy", >>>> which also don't show up when running a Cuttlefish-OSD: >>>> 15.65% [kernel] [k] >>>> intel_idle >>>> 7.20% libleveldb.so.1.9 [.] >>>> 0x3ceae >>>> 6.28% libc-2.11.3.so [.] >>>> memcmp >>>> 5.22% [kernel] [k] >>>> find_busiest_group >>>> 3.92% kvm [.] >>>> 0x2cf006 >>>> 2.40% libleveldb.so.1.9 [.] >>>> leveldb::InternalKeyComparator::Compar >>>> 1.95% [kernel] [k] >>>> _raw_spin_lock >>>> 1.69% [kernel] [k] >>>> default_send_IPI_mask_sequence_phys >>>> 1.46% libc-2.11.3.so [.] >>>> memcpy >>>> 1.17% libleveldb.so.1.9 [.] >>>> leveldb::Block::Iter::Next() >>>> 1.16% [kernel] [k] >>>> hrtimer_interrupt >>>> 1.07% [kernel] [k] >>>> native_write_cr0 >>>> 1.01% [kernel] [k] >>>> __hrtimer_start_range_ns >>>> 1.00% [kernel] [k] >>>> clockevents_program_event >>>> 0.93% [kernel] [k] >>>> find_next_bit >>>> 0.93% libstdc++.so.6.0.13 [.] >>>> std::string::_M_mutate(unsigned long, >>>> 0.89% [kernel] [k] >>>> cpumask_next_and >>>> 0.87% [kernel] [k] >>>> __schedule >>>> 0.85% [kernel] [k] >>>> _raw_spin_unlock_irqrestore >>>> 0.85% [kernel] [k] >>>> do_select >>>> 0.84% [kernel] [k] >>>> apic_timer_interrupt >>>> 0.80% [kernel] [k] >>>> fget_light >>>> 0.79% [kernel] [k] >>>> native_write_msr_safe >>>> 0.76% [kernel] [k] >>>> _raw_spin_lock_irqsave >>>> 0.66% libc-2.11.3.so [.] >>>> 0xdc6d8 >>>> 0.61% libpthread-2.11.3.so [.] >>>> pthread_mutex_lock >>>> 0.61% [kernel] [k] >>>> tg_load_down >>>> 0.59% [kernel] [k] >>>> reschedule_interrupt >>>> 0.59% libsnappy.so.1.1.2 [.] >>>> snappy::RawUncompress(snappy::Source*, >>>> 0.56% libstdc++.so.6.0.13 [.] std::string::append(char >>>> const*, unsig >>>> 0.54% [kvm_intel] [k] >>>> vmx_vcpu_run >>>> 0.53% [kernel] [k] >>>> copy_user_generic_string >>>> 0.53% [kernel] [k] >>>> load_balance >>>> 0.50% [kernel] [k] >>>> rcu_needs_cpu >>>> 0.45% [kernel] [k] fput >>>> >>>> >>>> Regards, >>>> >>>> Oliver >>>> >>>> On ma, 2013-08-26 at 23:33 -0700, Samuel Just wrote: >>>>> I just pushed a patch to wip-dumpling-log-assert (based on current >>>>> dumpling head). I had disabled most of the code in PGLog::check() but >>>>> left an (I thought) innocuous assert. It seems that with (at least) >>>>> g++ 4.6.3, stl list::size() is linear in the size of the list, so that >>>>> assert actually traverses the pg log on each operation. The patch in >>>>> wip-dumpling-log-assert should disable that assert as well by default. >>>>> Let me know if it helps. >>>>> >>>>> It should be built within an hour of this email. >>>>> -Sam >>>>> >>>>> On Mon, Aug 26, 2013 at 10:46 PM, Matthew Anderson >>>>> <manderson8787@xxxxxxxxx> wrote: >>>>>> Hi Guys, >>>>>> >>>>>> I'm having the same problem as Oliver with 0.67.2. CPU usage is >>>>>> around >>>>>> double that of the 0.61.8 OSD's in the same cluster which appears to >>>>>> be causing the performance decrease. >>>>>> >>>>>> I did a perf comparison (not sure if I did it right but it seems ok). >>>>>> Both hosts are the same spec running Ubuntu 12.04.1 (3.2 kernel), >>>>>> journal and osd data is on an SSD, OSD's are in the same pool with >>>>>> the >>>>>> same weight and the perf tests were run at the same time on a >>>>>> realworld load consisting of RBD traffic only. >>>>>> >>>>>> Dumpling - >>>>>> >>>>>> Events: 332K cycles >>>>>> 17.93% ceph-osd libc-2.15.so [.] 0x15d523 >>>>>> 17.03% ceph-osd ceph-osd [.] 0x5c2897 >>>>>> 4.66% ceph-osd ceph-osd [.] >>>>>> leveldb::InternalKeyComparator::Compare(leveldb::Slice const&, level >>>>>> 3.46% ceph-osd ceph-osd [.] >>>>>> leveldb::Block::Iter::Next() >>>>>> 2.70% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::string::_M_mutate(unsigned long, unsigned long, unsigned long) >>>>>> 2.60% ceph-osd ceph-osd [.] PGLog::check() >>>>>> 2.57% ceph-osd [kernel.kallsyms] [k] __ticket_spin_lock >>>>>> 2.49% ceph-osd ceph-osd [.] ceph_crc32c_le_intel >>>>>> 1.93% ceph-osd libsnappy.so.1.1.2 [.] >>>>>> snappy::RawUncompress(snappy::Source*, char*) >>>>>> 1.53% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::string::append(char >>>>>> const*, unsigned long) >>>>>> 1.47% ceph-osd libtcmalloc.so.0.1.0 [.] operator new(unsigned >>>>>> long) >>>>>> 1.33% ceph-osd [kernel.kallsyms] [k] >>>>>> copy_user_generic_string >>>>>> 0.98% ceph-osd libtcmalloc.so.0.1.0 [.] operator >>>>>> delete(void*) >>>>>> 0.90% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::string::assign(char >>>>>> const*, unsigned long) >>>>>> 0.75% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::string::_M_replace_safe(unsigned long, unsigned long, char cons >>>>>> 0.58% ceph-osd [kernel.kallsyms] [k] wait_sb_inodes >>>>>> 0.55% ceph-osd ceph-osd [.] >>>>>> leveldb::Block::Iter::Valid() const >>>>>> 0.51% ceph-osd libtcmalloc.so.0.1.0 [.] >>>>>> tcmalloc::ThreadCache::ReleaseToCentralCache(tcmalloc::ThreadCache:: >>>>>> 0.50% ceph-osd libtcmalloc.so.0.1.0 [.] >>>>>> tcmalloc::CentralFreeList::FetchFromSpans() >>>>>> 0.47% ceph-osd libstdc++.so.6.0.16 [.] 0x9ebc8 >>>>>> 0.46% ceph-osd libc-2.15.so [.] vfprintf >>>>>> 0.45% ceph-osd [kernel.kallsyms] [k] find_busiest_group >>>>>> 0.45% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::string::resize(unsigned long, char) >>>>>> 0.43% ceph-osd libpthread-2.15.so [.] pthread_mutex_unlock >>>>>> 0.41% ceph-osd [kernel.kallsyms] [k] iput_final >>>>>> 0.40% ceph-osd ceph-osd [.] >>>>>> leveldb::Block::Iter::Seek(leveldb::Slice const&) >>>>>> 0.39% ceph-osd libc-2.15.so [.] _IO_vfscanf >>>>>> 0.39% ceph-osd ceph-osd [.] >>>>>> leveldb::Block::Iter::key() const >>>>>> 0.39% ceph-osd libtcmalloc.so.0.1.0 [.] >>>>>> tcmalloc::CentralFreeList::ReleaseToSpans(void*) >>>>>> 0.37% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::basic_ostream<char, >>>>>> std::char_traits<char> >& std::__ostream_in >>>>>> >>>>>> >>>>>> Cuttlefish - >>>>>> >>>>>> Events: 160K cycles >>>>>> 7.53% ceph-osd [kernel.kallsyms] [k] __ticket_spin_lock >>>>>> 6.26% ceph-osd libc-2.15.so [.] 0x89115 >>>>>> 3.06% ceph-osd ceph-osd [.] ceph_crc32c_le >>>>>> 2.66% ceph-osd libtcmalloc.so.0.1.0 [.] operator new(unsigned >>>>>> long) >>>>>> 2.46% ceph-osd [kernel.kallsyms] [k] find_busiest_group >>>>>> 1.80% ceph-osd libtcmalloc.so.0.1.0 [.] operator >>>>>> delete(void*) >>>>>> 1.42% ceph-osd [kernel.kallsyms] [k] try_to_wake_up >>>>>> 1.27% ceph-osd ceph-osd [.] 0x531fb6 >>>>>> 1.21% ceph-osd libstdc++.so.6.0.16 [.] 0x9ebc8 >>>>>> 1.14% ceph-osd [kernel.kallsyms] [k] wait_sb_inodes >>>>>> 1.02% ceph-osd libc-2.15.so [.] _IO_vfscanf >>>>>> 1.01% ceph-osd [kernel.kallsyms] [k] update_shares >>>>>> 0.98% ceph-osd [kernel.kallsyms] [k] >>>>>> filemap_fdatawait_range >>>>>> 0.90% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::basic_ostream<char, >>>>>> std::char_traits<char> >& std >>>>>> 0.89% ceph-osd [kernel.kallsyms] [k] iput_final >>>>>> 0.79% ceph-osd libstdc++.so.6.0.16 [.] >>>>>> std::basic_string<char, >>>>>> std::char_traits<char>, std::a >>>>>> 0.79% ceph-osd [kernel.kallsyms] [k] >>>>>> copy_user_generic_string >>>>>> 0.78% ceph-osd libc-2.15.so [.] vfprintf >>>>>> 0.70% ceph-osd libtcmalloc.so.0.1.0 [.] >>>>>> tcmalloc::ThreadCache::ReleaseToCentralCache(tcmalloc: >>>>>> 0.69% ceph-osd [kernel.kallsyms] [k] __d_lookup_rcu >>>>>> 0.69% ceph-osd libtcmalloc.so.0.1.0 [.] >>>>>> tcmalloc::CentralFreeList::FetchFromSpans() >>>>>> 0.66% ceph-osd [kernel.kallsyms] [k] igrab >>>>>> 0.63% ceph-osd [kernel.kallsyms] [k] update_cfs_load >>>>>> 0.63% ceph-osd [kernel.kallsyms] [k] link_path_walk >>>>>> >>>>>> If you'd like some more tests run just let me know, more than happy >>>>>> to help >>>>>> >>>>>> Thanks >>>>>> -Matt >>>>> >>>> >>>> >>>> _______________________________________________ >>>> ceph-users mailing list >>>> ceph-users@xxxxxxxxxxxxxx >>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >>>> >>> >>> _______________________________________________ >>> ceph-users mailing list >>> ceph-users@xxxxxxxxxxxxxx >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >>> >> >> _______________________________________________ >> ceph-users mailing list >> ceph-users@xxxxxxxxxxxxxx >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com