[virt-tools-list] Default use of caching on raw volumes

Jamin W. Collins jcollins at asgardsrealm.net
Tue Aug 17 13:22:09 UTC 2010

On 08/17/2010 07:17 AM, Nikolai K. Bochev wrote:
> Well i just tried this ( i never really did read the documents on that
> part ) and amazingly my loadavg on the kvm host dropped by a factor of 10.
> All the load was coming out of a heavily loaded VM with pgsql in it that
> was writing all the time ( zabbix monitoring etc. ).
> I guess this should really be set as default, not sure if it's up to
> virt-manager or libvirt.

This is precisely my point.  With defaults the way they are right now, I 
suspect quite a few people will get the wrong impression of KVM's 
performance.  I've even found a significant performance increase with 
file backed VMs by disabling caching.

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