[sheepdog-users] cache performance test

[Liu Yuan]

On Tue, Jun 25, 2013 at 06:31:48PM +0800, Liu Yuan wrote:
> On Tue, Jun 25, 2013 at 12:16:15PM +0200, Valerio Pachera wrote:
> > sheep -w size=20000 /mnt/sheep/meta/,/mnt/sheep/dsk02
> > 
> > /mnt/sheep/meta is a ssd disk. Cache it stored here. No objects are
> > stored on the same physical disk.
> > /mnt/sheep/dsk02 is a mechanical sata disk, 7200 rpm like all the
> > other hdd of the cluster.
> > 
> > This is my guest
> >   qemu-system-x86_64 -enable-kvm -smp 2 -m 512 -drive
> > file=sheepdog:squeeze,cache=writeback -drive
> > file=sheepdog:big,cache=writeback
> > and is running on the node with the ssd.
> > 
> > vdi named 'big' is formatted with ext4 and is where is write.
> > 
> > I compare the write speed of the guest using cache, with the write
> > speed of the host writing directly on the ssd.
> > 
> > 
> > 
> > dd if=/dev/zero of=n bs=1M count=512 oflag=direct
> > 
> > Guest: 55 MB/s
> > Host: 130 MB/s
> > 
> 
> Please try following setup:
> 1 use vritio for guest, that is, -drive if=virtio at startup
> 2 echo 4096 > /sys/block/vda/queue/max_sectors_kb in the *guest*

You need to echo 4096 to every sheepdog device, vda,vdb,vdc...if any

> 3 use deadline io-sched for guest
> 
> With above setup, I guess the number will go higher.
> 

what is the number of the new test against above combination?

Thanks,
Yuan