Virtual machines use memory copies between the physical device and the guest OS. Clearly this is an area where more work is being done in the virtualization community but is outside the scope of the typical filesystem gfs or otherwise. You might ask about io performance tuning on the respective virtualization technology mailing list you use. Regards -steve On Wed, 2010-01-06 at 17:47 -0600, Paras pradhan wrote: > I have a GFS based shared storage cluster that connects to SAN by > fibre channel. This GFS shared storage hold several virtual machines. > While running hdparam from the host to a GFS share, I get following > results. > > > -- > hdparm -t /guest_vms1 > > > /dev/mapper/test_vg1-prd_vg1_lv: > Timing buffered disk reads: 262 MB in 3.00 seconds = 87.24 MB/sec > --- > > > > > Now from within the virtual machines, the I/O is low > > > --- > hdparm -t /dev/mapper/VolGroup00-LogVol00 > > > /dev/mapper/VolGroup00-LogVol00: > Timing buffered disk reads: 88 MB in 3.00 seconds = 29.31 MB/sec > --- > > > I am looking for possibilities if I can increase my I/O read write > within my virtual machines. Tuning GFS does help in this case? > > > Sorry if my question is not relevant to this list > > > > > Thanks > Paras. > > > > > > > > > -- > Linux-cluster mailing list > Linux-cluster@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/linux-cluster -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
