Re: Huge Data sets, simple queries - Mailing list pgsql-performance

From Mike Rylander
Subject Re: Huge Data sets, simple queries
Date
Msg-id b918cf3d0602010957n7d0ba9cetb290a0cda1b951d0@mail.gmail.com
Whole thread Raw
In response to Re: Huge Data sets, simple queries  ("Luke Lonergan" <llonergan@greenplum.com>)
List pgsql-performance
On 2/1/06, Luke Lonergan <llonergan@greenplum.com> wrote:
[snip]
> This is actually interesting overall - I think what this might be showing is
> that the Linux SW RAID1 is alternating I/Os to the mirror disks from
> different processes (LWP or HWP both maybe?), but not within one process.

I can confirm this behavior after looking at my multipathed fibre
channel SAN.  To the best of my knowledge, the multipathing code uses
the same underlying I/O code as the Linux SW RAID logic.

--
Mike Rylander
mrylander@gmail.com
GPLS -- PINES Development
Database Developer
http://open-ils.org

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