Date: Fri, 1 Feb 2008 09:24:15 +0100 From: "Claus Guttesen" <kometen@gmail.com> To: "Niki Denev" <nike_d@cytexbg.com> Cc: freebsd-performance@freebsd.org Subject: Re: postgresql-performance using sysbench Message-ID: <b41c75520802010024n71c840a4kb6531a8cce2d4a0f@mail.gmail.com> In-Reply-To: <2e77fc10801310826v2fabb5g594840241784fc7@mail.gmail.com> References: <b41c75520801280701x35e628dk90841b55cac77045@mail.gmail.com> <479E3C5E.1070405@FreeBSD.org> <b41c75520801281246q16d305ecue915e66bea6ac5ab@mail.gmail.com> <fnmrri$pi4$1@ger.gmane.org> <b41c75520801290146g4e6e2c17oe2fc432245253ba7@mail.gmail.com> <47A043FD.9090607@FreeBSD.org> <fnpjvo$n8i$1@ger.gmane.org> <47A0CD11.802@FreeBSD.org> <9bbcef730801301157n25684018y3d43bfdd0301a8dd@mail.gmail.com> <2e77fc10801310826v2fabb5g594840241784fc7@mail.gmail.com>
next in thread | previous in thread | raw e-mail | index | archive | help
> Just a thought on the effect that HZ has on filesystem (and overall)
> performance :
> Linux has sort of backtracked from defaulting to HZ=1000 and enable it
> only on kernels compiled
> for "Desktop" work, and setting HZ=250 for the "Server" profile.
I'm doing some db-imports on postgresql on a file which takes 3 hours
and 40 min. with default HZ (1000). Then I changed HZ to 250 (in
loader.conf) and rebooted. The import still took 3 h. 40 min. so
altering HZ does not seem to have any influence.
#>sysctl kern.clockrate
kern.clockrate: { hz = 250, tick = 4000, profhz = 166, stathz = 33 }
--
regards
Claus
When lenity and cruelty play for a kingdom,
the gentlest gamester is the soonest winner.
Shakespeare
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?b41c75520802010024n71c840a4kb6531a8cce2d4a0f>