Re: [Xen-devel] xm commands run very slow .... - Himanshu Raj - com.xensource.lists.xen-devel

5 messages in com.xensource.lists.xen-develRe: [Xen-devel] xm commands run very ...

From	Sent On	Attachments
Himanshu Raj	25 Jan 2006 06:18
Ewan Mellor	25 Jan 2006 10:05
Himanshu Raj	25 Jan 2006 14:06
Himanshu Raj	25 Jan 2006 16:36
Himanshu Raj	25 Jan 2006 18:29

Subject:	Re: [Xen-devel] xm commands run very slow ....
From:	Himanshu Raj (rh...@cc.gatech.edu)
Date:	01/25/2006 04:36:41 PM
List:	com.xensource.lists.xen-devel

top shows heavy activity by xenstored for a long time (like 30-40% CPU
utilization). Also there is a huge gap between xenstore write and devcontroller to kick in. Excerpt from xend.log follows:

[2006-01-25 19:22:48 xend.XendDomainInfo] DEBUG (XendDomainInfo:688) Storing dom ain details: {'console/ring-ref': '124478', 'console/port': '2', 'name': 'vm1', 'console/limit': '1048576', 'vm': '/vm/c1b17d02-ed25-f67e-2bef-0bbed31d765f', 'd omid': '1', 'cpu/0/availability': 'online', 'memory/target': '65536', 'store/rin g-ref': '124479', 'store/port': '1'} [2006-01-25 19:23:00 xend] DEBUG (DevController:132) Waiting for devices vif. [2006-01-25 19:23:00 xend] DEBUG (DevController:132) Waiting for devices usb. [2006-01-25 19:23:01 xend] DEBUG (DevController:132) Waiting for devices vbd.

Does it ring any bells?

Best regards, Himanshu

On Wed, Jan 25, 2006 at 05:06:36PM -0500, Himanshu Raj wrote:

Thanks Ewan.

I also saw one more discrepency which might be the root of this problem. When I do xend start on first machine, 8 processes start up (i.e. ps aux | grep xend shows actually 8 proceeses). On my other machine, I see only 2 processes. Do you think it is the problem?

-Himanshu

I know it is kind of vague problem, but I am banking of somebody seeing the exact thing.

I have two machines with everything identical, except on one machine I compile xen and on other I just use the binaries compiled on the previous machine.

Now on first machine, where I compile everything, xm invocation is veeeeeeeeeery slow. Although it doesn't seem to be "system" problem. Look at a time xm list invocation: real 32s user .2s sys .02s

On another machine the real time is very close to user+sys.

I just can't comprehend why this is going on. Any clues will be deeply
appreciated.

xm is a client to Xend, talking over HTTP -- xm is simply blocking for 30 seconds waiting for the server -- you need to figure out why the server is spinning or stalling.

/var/log/xend.log may help. top may help also.

Ewan.

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