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[Xen-users] Asynchronous IO

To: Xen-users@xxxxxxxxxxxxxxxxxxx
Subject: [Xen-users] Asynchronous IO
From: Priya PM <pmpriya@xxxxxxxxx>
Date: Wed, 7 Sep 2005 16:24:47 -0600
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Hi,
 
I have installed Xen on Linux 2.6.11.10 and i am trying to do Asynchronous Direct IO on SAS drives. The application which does the asynchronous direct io on SAS drive is running on Domain 0. Actually the IOPs what i get for a 512Bytes IO size is 67, but if i do the same operation on Linux 2.6.11.10 native kernel, i get 267 IOPs.Can anyone tell me why this huge differnece? Am i missing something? In the current setup on Xen, if i do Synchronous IO, then i am getting 265 IOPs which is expected. So i am wondering why Asynchronous IO should behave this way? Is there any reason??
 
Thanks,
Priya
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