X-Original-To: pgsql-general-postgresql.org@localhost.postgresql.org Received: from localhost (mx1.hub.org [200.46.208.251]) by postgresql.org (Postfix) with ESMTP id 7178C9F96B6 for ; Wed, 10 May 2006 03:49:09 -0300 (ADT) Received: from postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.208.251]) (amavisd-new, port 10024) with ESMTP id 47206-10 for ; Wed, 10 May 2006 03:49:03 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey- Received: from peufeu.com (boutiquenumerique.com [82.67.9.10]) by postgresql.org (Postfix) with ESMTP id B11A49F931D for ; Wed, 10 May 2006 03:49:02 -0300 (ADT) Received: (qmail 20828 invoked from network); 10 May 2006 08:50:24 +0200 Received: from boutiquenumerique.com (HELO apollo13) (82.67.9.10) by boutiquenumerique.com with SMTP; 10 May 2006 08:50:24 +0200 Date: Wed, 10 May 2006 08:50:22 +0200 To: 7ukwn@free.fr, "Hannes Dorbath" Subject: Re: [PERFORM] Arguments Pro/Contra Software Raid Cc: pgsql-general@postgresql.org, pgsql-performance@postgresql.org References: <44606A98.4090705@free.fr> From: PFC Content-Type: text/plain; format=flowed; delsp=yes; charset=utf-8 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID: In-Reply-To: <44606A98.4090705@free.fr> User-Agent: Opera M2/8.51 (Linux, build 1462) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200605/418 X-Sequence-Number: 95210 > 2b- LARGE UPS because HDs are the components that have the higher power > consomption (a 700VA UPS gives me about 10-12 minutes on a machine > with a XP2200+, 1GB RAM and a 40GB HD, however this fall to...... > less than 25 secondes with seven HDs ! all ATA), I got my hands on a (free) 1400 VA APC rackmount UPS ; the batteries were dead so I stuck two car batteries in. It can power my computer (Athlon 64, 7 drives) for more than 2 hours... It looks ugly though. I wouldn't put this in a server rack, but for my home PC it's perfect. It has saved my work many times... Harddisks suck in about 15 watts each, but draw large current spikes on seeking, so the VA rating of the UPS is important. I guess in your case, the batteries have enough charge left; but the current capability of the UPS is exceeded. > Some hardware ctrlrs are able to avoid the loss of a disk if you turn > to have some faulty sectors (by relocating internally them); software > RAID doesn't as sectors *must* be @ the same (linear) addresses. Harddisks do transparent remapping now... linux soft raid can rewrite bad sectors with good data and the disk will remap the faulty sector to a good one.