Re: [Xen-devel] Re: Improving hvm IO performance by using self IO emulator (YA io-emu?) - Alan - com.xensource.lists.xen-devel

22 messages in com.xensource.lists.xen-develRe: [Xen-devel] Re: Improving hvm IO ...

From	Sent On	Attachments
Tristan Gingold	21 Feb 2007 21:22
Keir Fraser	21 Feb 2007 23:59
tgin...@free.fr	22 Feb 2007 01:33
Keir Fraser	22 Feb 2007 02:23
Guy Zana	22 Feb 2007 02:33
Anthony Liguori	22 Feb 2007 08:05
tgin...@free.fr	22 Feb 2007 12:58
Anthony Liguori	22 Feb 2007 13:22
Mark Williamson	22 Feb 2007 13:23
Anthony Liguori	22 Feb 2007 13:32
Mark Williamson	22 Feb 2007 13:40
Anthony Liguori	22 Feb 2007 16:12
Mark Williamson	22 Feb 2007 16:15
Alan	22 Feb 2007 16:26
Alan	22 Feb 2007 16:31
Alan	23 Feb 2007 04:57
Anthony Liguori	23 Feb 2007 10:55
Tristan Gingold	23 Feb 2007 22:06
Tristan Gingold	23 Feb 2007 22:12
Tristan Gingold	23 Feb 2007 22:17
Tristan Gingold	23 Feb 2007 22:19
Mark Williamson	27 Feb 2007 04:13

Subject:	Re: [Xen-devel] Re: Improving hvm IO performance by using self IO emulator (YA io-emu?)
From:	Alan (al...@lxorguk.ukuu.org.uk)
Date:	02/22/2007 04:31:51 PM
List:	com.xensource.lists.xen-devel

Can SATA drives queue multiple outstanding requests? Thought some newer rev could, but I may well be misremembering - in any case we'd want something that was well supported.

Most SATA drives support NCQ which is sensible queuing and all the rest of it. Some early ones get it badly wrong. You need a controller interface that handles it and a device that handles it. Devices pretending to be PATA controllers lack the brains but AHCI is a current intel standard used by many vendors for this role and intended to replace SFF style IDE.

Alam