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RAID Syncronisation time in VM

Posted: 11. Oct 2009, 04:48
by tb2571989
Hi,

I'm running a Server 2003 VM (with additions) and have a 60GB IDE hard disk and 4x 80GB SATA disks with the 4 SATA's counfigured as RAID 5. I noticed the syncronisation time is excrucatingly slow (probably 10% every 15 minutes). Is this the same speed if I were doing it for real? Does the size of the disks matter, i.e. would it take a RAID with 1TB disks the same time as a RAID with 100GB?

My VB is 3.0.6 (but downloading 3.0.8 now). The VM is S2003 with 1GB RAM and Host is Vista Pro. Thanks.

Re: RAID Syncronisation time in VM

Posted: 11. Oct 2009, 13:42
by vbox4me2
Are you talking about raid on the Host with a VDI stored on it or a software raid on the Guest with 4/5 vdi disks?

Re: RAID Syncronisation time in VM

Posted: 11. Oct 2009, 13:55
by Sasquatch
I'm guessing the latter, makes more sense since he's talking about RAID on Server 2003, which he runs in a VM. So in that case, it would be software RAID.

Since everything needs to be done through the driver in software mode, have you ever looked at the CPU usage of your Host and Guest?

Re: RAID Syncronisation time in VM

Posted: 11. Oct 2009, 15:50
by tb2571989
I mean RAID on the Host, sorry.

The CPU usage of the guest is at about 45-60% and of the host about 80-95%.

Re: RAID Syncronisation time in VM

Posted: 11. Oct 2009, 15:56
by vbox4me2
Then what is the Guest doing with the raid??? a VM doesn't see raid hardware percee, unless you managed to get raid management software to load on the Guest to control the Host raid hardware. It still isnt clear what your doing.

Re: RAID Syncronisation time in VM

Posted: 11. Oct 2009, 16:33
by tb2571989
Server 2003 has built in raid software, so I was wondering how long it takes for a raid to syncronise. Is it the same in real life as in a VM?

Re: RAID Syncronisation time in VM

Posted: 11. Oct 2009, 16:37
by vbox4me2
That all depends how fast the Host is with disk IO, haven't really tested this as I depend on raid to be managed by the Host.