Subject: Re: vmware periodic freeze
To: Manuel Bouyer <bouyer@antioche.lip6.fr>
From: Christian Groessler <cpg@aladdin.de>
List: port-i386
Date: 07/14/2001 00:28:25
On 07/13/2001 11:44:34 PM ZE2 Manuel Bouyer wrote:
>
>On Fri, Jul 13, 2001 at 11:05:13PM +0200, Christian Groessler wrote:
>>
>> About every 3 seconds the vmware machine freezes for about 3
>> seconds.
>> While this happens one of the vmware processes is in a function
>> "xscmd".
>> Here's the ps axl line:
>>
>>    0 363  360   0  -6 -19  3092   1992 xscmd    D<L  ?? 0:00.13
>>    /emul/linux/usr/local/bin/vmware -q notesnt/vm-nt.cfg
>>
>> I cannot find this xscmd function, a nm /netbsd | grep xscmd reveils
>> nothing.
>
>This is in the scsipi code. Your process is waiting for a SCSI or ATAPI
>command to complete.

But why didn't I find the name in /netbsd? I'm still curious where ps
got it from.

>
>Do you have a CD or ZIP drive ? Does vmware try to use it ?
>I suspect it is try to access CD or ZIP (maybe just a Test Unit Ready) and
>as the drive is empty the command takes some time to complete.

Yes! Yes! Yes! This was the reason. I disabled the CDROM in the vmware
configuration and now the NT4 VM is working fine!  Thanks!

But, I'm sorry to say, there still seems to be a problem/quirk in NetBSD
VMWare. The drive wasn't empty (but the drive is really cheap). It
takes this delay when accessing it (mounting and reading data) on both
Linux and NetBSD native.
So this explains the delay. But using the same vmware configuration,
running it on Linux this delay (freeze) doesn't happen.
Either on Linux these (VMWare/NT4?) device accesses are cached or
don't affect the machine this heavily?

regards,
chris