Date: Sun, 24 Mar 2013 10:51:15 -0700 From: Adrian Chadd <adrian@freebsd.org> To: Adam Vande More <amvandemore@gmail.com> Cc: Daniel Bilik <daniel.bilik@neosystem.cz>, freebsd-performance@freebsd.org Subject: Re: FreeBSD 9.1 vs CentOS 6.3 Message-ID: <CAJ-VmomOYkAj=1NuQbk3Wh5dTrE7_KceWG=qesT3FA7fcZKMdg@mail.gmail.com> In-Reply-To: <CA%2BtpaK3iZfBD3RgOFSLKss_3=oQT75q=5cswDSrmkrMLKWOcjg@mail.gmail.com> References: <514C1E5F.8040504@contactlab.com> <20130323213406.93cc3baddf69d5d71f10365e@neosystem.cz> <CA%2BtpaK2JK3xhEc_RrOCAdEB1vvapEHE=VqvY5=kSM-Bkhy07PA@mail.gmail.com> <CA%2BtpaK3iZfBD3RgOFSLKss_3=oQT75q=5cswDSrmkrMLKWOcjg@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
The contention is due to memory allocations being page aligned and those pools all hitting the same cache line mappings. Adrian On 24 March 2013 09:09, Adam Vande More <amvandemore@gmail.com> wrote: > I think increasing the number of arenas may help the contention, eg "ln -s > 3N /etc/malloc.conf" > > On Sun, Mar 24, 2013 at 11:01 AM, Adam Vande More <amvandemore@gmail.com>wrote: > >> These are interesting results. Did you try tuning any of the jemalloc >> options in /etc/malloc.conf? >> >> >> On Sat, Mar 23, 2013 at 3:34 PM, Daniel Bilik <daniel.bilik@neosystem.cz>wrote: >> >>> On Fri, 22 Mar 2013 10:03:27 +0100 >>> Davide D'Amico <davide.damico@contactlab.com> wrote: >>> >>> > Hi, I'm doing performance tests on a DELL R720, follows dmesg: >>> > ... >>> > I will use this server as a mysql-5.6 dbserver so I have a root >>> > partition using a hw raid1 and a /DATAZFS partition, follows >>> > configuration: >>> > ... >>> >>> Well, it seems to be interesting coincidence... We've just finished >>> benchmarking MySQL with various (m)allocators. The goal was to test >>> tcmalloc, but when the system was up and running, we've taken the >>> opportunity to benchmark also other alternatives... including jemalloc. >>> All tests were performed on default MySQL 5.5.28 running on Debian Wheezy. >>> Between the tests nothing was touched on the machine or the system, just >>> allocators were changed (ie. mysqld restarted). >>> >>> Results for different test modes are available here... >>> >>> http://neosystem.cz/benchmark/mysql/ >>> >>> It seems there is notable performance penalty for read-only transactions >>> when MySQL is using jemalloc. The more concurrent threads are running, the >>> more is jemalloc losing to other allocators. The penalty is also there for >>> read-write transactions, but not that significant (error bars in the >>> histograms also show that results for read-write tests tend to be very >>> unstable). OTOH in non-transactional tests, jemalloc seems to be in par >>> with others, and under specific load can even outperform some of them. >>> >>> In your original post, there is not mentioned in what mode you've >>> performed >>> OLTP test, but according to numbers I suspect it was "complex", ie. >>> transactional. Can you repeat tests (both on CentOS and FreeBSD) with >>> --oltp-test-mode=nontrx and/or simple? >>> >>> -- >>> Daniel Bilik >>> neosystem.cz >>> _______________________________________________ >>> freebsd-performance@freebsd.org mailing list >>> http://lists.freebsd.org/mailman/listinfo/freebsd-performance >>> To unsubscribe, send any mail to " >>> freebsd-performance-unsubscribe@freebsd.org" >>> >> >> >> >> -- >> Adam Vande More > > > > > -- > Adam Vande More > _______________________________________________ > freebsd-performance@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-performance > To unsubscribe, send any mail to "freebsd-performance-unsubscribe@freebsd.org"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAJ-VmomOYkAj=1NuQbk3Wh5dTrE7_KceWG=qesT3FA7fcZKMdg>