Do you guys have any updates on this? --
regards gezeala bacuño II On Tue, Apr 22, 2014 at 11:52 PM, Palle Girgensohn <gir...@pingpong.net>wrote: > > > > 23 apr 2014 kl. 01:04 skrev Adrian Chadd <adr...@freebsd.org>: > > > > Hi, > > > > Are you able to repeat these tests (for both 9.2 and 9.3) whilst > > grabbing some performance data from lock profiling and hwpmc? > > I sure can, but I'd love some pointers as to how this is done. Please? :-) > > > > > The benchmarking is great but it doesn't tell us enough information as > > to "why" things behave poorly compared to Linux and why the mmap drop > > isn't so great. > > > As per the discussion on postresql-hackers, the regression between pg9.2 > and pg9.3, which includes the sysv->mmap shift, *might* also exist, at > least partly, on Linux as well. > > The initial post in *this* thread does however indicate that freebsd > performs poorer than Linux and dragonflybsd, but does not really compare > PostgreSQL versions. > > Just so we're not pursuing the wrong problem here, let's be open minded > about the definition of the problem. :-) > > > > > What about with more clients? 64? 128? 256? > > My test went to 80. I can go higher as well, though other sources say 50 > is a reasonable limit for PostgreSQL. > > Palle > > > > > > > > Thanks! > > > > > > > > -a > > > > > >> On 21 April 2014 14:11, Palle Girgensohn <gir...@pingpong.net> wrote: > >> > >> > >>> Den torsdagen den 20:e mars 2014 kl. 00:33:10 UTC+1 skrev Sean > Chittenden: > >>> > >>>> As far as I know, the test was done on both UFS2 and ZFS and the > >>>> difference was marginal. > >>> > >>> As Adrian pointed out, there is an mmap(2) mutex in the way. Starting > in > >>> PostgreSQL 9.3, shared buffers are allocated out of mmap(2) instead of > shm. > >>> shm is only used to notify the PostgreSQL postmaster that a child > process > >>> exited/crashed (when a pid detaches from a shm segment, there is a > kernel > >>> event, but there is no kernel event when detaching from an mmap(2) > region). > >>> -sc > >>> > >>> http://www.postgresql.org/docs/9.3/static/release-9-3.html#AEN115039 > >>> > >>> > >>>>>> Just want to share these pgbench results done by DragonFlyBSD, and > >>> would > >>>>>> like some input on why these numbers look so bad and what can be > done > >>> to > >>>>>> improve (ie. kernel tunables etc) the performance. > >>> > http://lists.dragonflybsd.org/pipermail/users/attachments/20140310/4250b961/attachment-0001.pdf > >>>>> > >>>>> > >>>>> Do you have the ability to test with FreeBSD 8.x and 9.x to see if > this > >>> is > >>>>> regression? > >>>>> > >>>>> Also you don't mention the FS used in each case, so I'm wondering if > >>> you > >>>>> used a ZFS install of FreeBSD which could help to explain things. > >>> > >>> > >>> -- > >>> Sean Chittenden > >>> se...@chittenden.org <javascript:> > >> Hi, > >> > >> There is a fresh thread about this in postgresql-hackers [1]. > >> > >> There are two parallel approaches suggested there, where one is to have > an > >> option to continue using the old SYSV shared memory in PostgreSQL, and > the > >> other is the suggestion that "somebody needs to hold the FreeBSD folks' > >> feet to the fire about when we can expect to see a fix from their side." > >> > >> Looking at the original post in this thread, it seems to me that FreeBSD > >> has scalability problems beyond what the SYSV vs mmap change in > PostgreSQL > >> introduces? Check my test of PostgreSQL 9.2 vs 9.3 on FreeBSD 10.0 at > [1]. > >> The difference between PG92 and PG93 is not huge, ~17%. The difference > >> between FreeBSD and the other OS:es in this thread's original post's > >> performance chart seems to be about a lot more? > >> > >> Palle > >> > >> [1] > >> > http://www.postgresql.org/message-id/2ae143d2-87d3-4ad1-ac78-ce2258230...@freebsd.org > >> _______________________________________________ > >> 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" > _______________________________________________ > 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" > _______________________________________________ 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"
