My experience is that disabling swap and turning off zone_reclaim_mode gets rid of any real problem for a large memory postgresql database server. While it would be great to have a NUMA aware pgsql, I question the solidity and reliability of the current linux kernel implementation in a NUMA evironment, especially given the poor behaviour of the linux kernel as regards swap behaviour. On Tue, Jul 24, 2012 at 3:23 PM, John Lister <john.lister@xxxxxxxxxxxxx> wrote: > On 24/07/2012 21:12, Claudio Freire wrote: >> >> On Tue, Jul 24, 2012 at 3:41 PM, Claudio Freire <klaussfreire@xxxxxxxxx> >> wrote: >>> >>> On Tue, Jul 24, 2012 at 3:36 PM, John Lister <john.lister@xxxxxxxxxxxxx> >>> wrote: >>>> >>>> Do you have a suggestion about how to do that? I'm running Ubuntu 12.04 >>>> and >>>> PG 9.1, I've modified pg_ctlcluster to cause pg_ctl to use a wrapper >>>> script >>>> which starts the postmaster using a numactl wrapper, but all subsequent >>>> client processes are started with interleaving enabled as well. Any >>>> ideas >>>> how to make just the postmaster process start with interleaving? >>> >>> postmaster should call numactl right after forking: >>> http://linux.die.net/man/2/set_mempolicy >> >> Something like the attached patch (untested) > > Cheers, I'll give it a go, I wonder if this is likely to be integrated into > the main code? As has been mentioned here before, postgresql isn't as badly > affected as mysql for example, but I'm wondering if the trend to larger > memory and more cores/nodes means it should be offered as an option? > Although saying that I've read that 10Gb of shared buffers may be enough > even in big machines 128+Gb ram.. > > Thoughts? > > John > > > > > -- > Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-performance -- To understand recursion, one must first understand recursion. -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
