Received: from localhost (unknown [200.46.204.187]) by postgresql.org (Postfix) with ESMTP id E07329F9DDB for ; Thu, 20 Sep 2007 20:04:10 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.187]) (amavisd-maia, port 10024) with ESMTP id 85947-02 for ; Thu, 20 Sep 2007 20:04:00 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.5 Received: from noel.decibel.org (noel.decibel.org [67.100.216.10]) by postgresql.org (Postfix) with ESMTP id C239F9F9A97 for ; Thu, 20 Sep 2007 20:04:04 -0300 (ADT) Received: by noel.decibel.org (Postfix, from userid 1001) id DECCA56450; Thu, 20 Sep 2007 23:04:02 +0000 (UTC) Received: (hashcash-sendmail, from uid 1001); Thu, 20 Sep 2007 18:04:01 -0500 Date: Thu, 20 Sep 2007 18:04:01 -0500 From: Decibel! To: pgsql-performance@postgresql.org Subject: Linux mis-reporting memory Message-ID: <20070920230400.GM95343@decibel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="fUvfsPTz/SzOZDdw" Content-Disposition: inline X-Operating-System: FreeBSD 6.1-RELEASE-p10 amd64 X-Distributed: Join the Effort! http://www.distributed.net User-Agent: Mutt/1.5.13 (2006-08-11) X-Hashcash: 1:20:070920:pgsql-performance@postgresql.org::j+lHVXKjMvIORDJ9:00000 000000000000000000000000Cm/i X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200709/341 X-Sequence-Number: 26886 --fUvfsPTz/SzOZDdw Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Sorry, I know this is probably more a linux question, but I'm guessing that others have run into this... I'm finding this rather interesting report from top on a Debian box... Mem: 32945280k total, 32871832k used, 73448k free, 247432k buffers Swap: 1951888k total, 42308k used, 1909580k free, 30294300k cached PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 12492 postgres 15 0 8469m 8.0g 8.0g S 0 25.6 3:52.03 postmaster 7820 postgres 16 0 8474m 4.7g 4.7g S 0 15.1 1:23.72 postmaster 21863 postgres 15 0 8472m 3.9g 3.9g S 0 12.4 0:30.61 postmaster 19893 postgres 15 0 8471m 2.4g 2.4g S 0 7.6 0:07.54 postmaster 20423 postgres 17 0 8472m 1.4g 1.4g S 0 4.4 0:04.61 postmaster 26395 postgres 15 0 8474m 1.1g 1.0g S 1 3.4 0:02.12 postmaster 12985 postgres 15 0 8472m 937m 930m S 0 2.9 0:05.50 postmaster 26806 postgres 15 0 8474m 787m 779m D 4 2.4 0:01.56 postmaster This is a machine that's been up some time and the database is 400G, so I'm pretty confident that shared_buffers (set to 8G) should be completely full, and that's what that top process is indicating. So how is it that linux thinks that 30G is cached? --=20 Decibel!, aka Jim C. Nasby, Database Architect decibel@decibel.org=20 Give your computer some brain candy! www.distributed.net Team #1828 --fUvfsPTz/SzOZDdw Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.3 (FreeBSD) iD8DBQFG8vxgdO30qud8SkgRAk+YAJ9VLw0ylRr2Q8pVxdVZoiaHEOKoKACgstpA MIDIr6HbSTpHec+5MYuBVbo= =I/TH -----END PGP SIGNATURE----- --fUvfsPTz/SzOZDdw--