jemalloc also has concurrency issues when threads > areas: http://people.freebsd.org/~jasone/jemalloc/bsdcan2006/jemalloc.pdf
On Sun, Mar 24, 2013 at 12:51 PM, Adrian Chadd <adr...@freebsd.org> wrote: > 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 <amvandem...@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 <amvandem...@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.bi...@neosystem.cz>wrote: > >> > >>> On Fri, 22 Mar 2013 10:03:27 +0100 > >>> Davide D'Amico <davide.dam...@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-unsubscr...@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-unsubscr...@freebsd.org" > -- 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-unsubscr...@freebsd.org"
