Re: H/W RAID 5 on slower disks versus no raid on faster HDDs

From: Chris Ruprecht <chris(at)ruprecht(dot)org>
To: <pgsql-admin(at)postgresql(dot)org>
Subject: Re: H/W RAID 5 on slower disks versus no raid on faster HDDs
Date: 2002-11-26 16:07:43
Message-ID: 200211261107.43333.chris@ruprecht.org
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-admin

Hi all,

On Monday 25 November 2002 05:43, Sander Steffann wrote:
> Hi,
>
> > In a production environment I would always favor some
> > kind of error protection. Either RAID 5 or RAID 1
> > (mirroring). A hardware RAID controller is faster than
> > software RAID.
>
> Considering the speed of CPU's and busses these days, software RAID can be
> a lot faster than hardware RAID in many cases. I prefer hardware RAID
> myself because of the simplicity (the OS doesn't need to know about the
> RAID configuration), but I hear good results from people running on
> software RAID.

Stability is an issue here. While the OS might get a code corruption in the
kernel by who-knows-what, this is less likely to happen in the on-board
memory (RAM/ROM) of the RAID controller.
If the system crashes for whatever reason, who knows what gets written back to
the disks. Most likely nothing, since the OS already died. Your RAID
controller will most likely still flush it's buffers back to disk and leave
everything as good as it gets.

just my 2c.

Best regards,
Chris

--
Network Grunt and Bit Pusher extraordinaire

In response to

Browse pgsql-admin by date

  From Date Subject
Next Message mallah 2002-11-26 17:25:13 pg_dump 7.3rc1 with 7.2 server.
Previous Message mallah 2002-11-26 16:05:35 Re: Starting the database server (2)