I’m guessing Yes based on this:
[root@xen1 ~]# cat /etc/modprobe.conf |
alias scsi_hostadapter ahci
alias scsi_hostadapter1 usb-storage
Is this good for me or bad?
From: Teck Choon Giam
Sent: Tuesday, December 14, 2010
To: Russ Purinton
Cc: Roberto Bifulco;
Subject: Re: [Xen-users] Sharing
Disk Access Time
On Wed, Dec 15, 2010 at 2:16 AM, Russ Purinton <rpurinton@xxxxxxxxxxxxxxxxxxxxxxx>
It appears Roberto has gone far beyond any testing I’ve ever done,
but I’ve always been concerned about disk access. I have a Xen server
with RAID 1 SATA drives internal using img files. The host is CentOS 5.5.
I notice that whenever I build a new VM and it gets to where it is
allocating the img file, the entire time it is allocating the space for it, all
my other virtual machines effectly stop doing anything.
One DomU is a windows terminal server. While logged into it,
I started the Image allocation then tried to open MS Outlook on the terminal
server. Everything hung until the disk allocation was completed, then
Outlook finally opened 30 minutes later.
Is there a way to do ‘fair-sharing’ of disk IO time so that a
single DomU cannot hog all the physical IO capacity?
Just curious... ... are you using AHCI mode?
Command to check:
# cat /etc/modprobe.conf | grep scsi_hostadapter
Giam Teck Choon