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"
