Re: KVM on top of BTRFS

2012-06-15 Thread steamraven
A couple tests have been uploaded to http://openbenchmarking.org/result/1206152- STEA-VMTESTS05. Note for the nodatacow, the subvolume did have a snapshot, since the point was for VM's that could be snapshoted (either through virsh or btrfs). Thus the first write to a block was cow, but

Re: KVM on top of BTRFS

2012-06-13 Thread Ernst Sjöstrand
Hi, you can't beat the benchmarks that Serge Hallyn did, really thorough! http://s3hh.wordpress.com/2012/05/02/first-round-of-kvm-performance-tests/ Regards //Ernst 2012/6/12 steamraven steamra...@yahoo.com: Seems a little unfair on btrfs to just to look at absolutes in this context. Prior

Re: KVM on top of BTRFS

2012-06-13 Thread steamraven
Ernst Sjöstrand ernstp at gmail.com writes: Hi, you can't beat the benchmarks that Serge Hallyn did, really thorough! http://s3hh.wordpress.com/2012/05/02/first-round-of-kvm-performance-tests/ They do seem very thorough. Unfortunately, they are kvm on top of ext4 and he was mainly

Re: KVM on top of BTRFS

2012-06-12 Thread Roman Mamedov
On Mon, 11 Jun 2012 23:53:34 + (UTC) Alex a...@bpmit.com wrote: Running KVM image files on btrfs as of yesterday. Used mkfs.btrfs -l 32k -n 32k to create and default options only (no mount options bar defaults, so no compression (just asking for trouble!), or autodefrag). 3.4.1 official

Re: KVM on top of BTRFS

2012-06-12 Thread Hubert Kario
On Monday 11 of June 2012 23:53:34 Alex wrote: Matthew Hawn steamraven at yahoo.com writes: What are the recommendations for running KVM images on BTRFS systems using Install: virt-install --connect qemu:///system -n china -r 256 --disk path=/var/lib/libvirt/images/china.img,size=4 -c

Re: KVM on top of BTRFS

2012-06-12 Thread Alex
Roman Mamedov rm at romanrm.ru writes: (Machine has no other load at all) No material difference between cache types (none, writeback and writethrough) when I tried. I had been using partition based KVM which is obviously going to be much faster. Seems a little unfair on btrfs to just to look

Re: KVM on top of BTRFS

2012-06-12 Thread Alex
Hubert Kario hka at qbs.com.pl writes: From what I heard, this is caused by slow KVM CD virtualisation. Try to install it and do some tests then. You read my mind :-) -- To unsubscribe from this list: send the line unsubscribe linux-btrfs in the body of a message to

Re: KVM on top of BTRFS

2012-06-12 Thread steamraven
Seems a little unfair on btrfs to just to look at absolutes in this context. Prior reports said that the fs ground to a halt, it isn't doing that by any stretch. I agree. What I am mostly looking for is the best setup for using KVM snapshots: KVM qcow2 on top of something like ext4 or

Re: KVM on top of BTRFS

2012-06-11 Thread Alex
Matthew Hawn steamraven at yahoo.com writes: What are the recommendations for running KVM images on BTRFS systems using kernel 3.4?  I saw older posts on the web complaining about poor performance, but I know a lot of work has gone into btrfs since then.  There also seemed to be the nocow

Re: KVM on top of BTRFS

2012-06-11 Thread dima
On 06/12/2012 08:53 AM, Alex wrote: Matthew Hawn steamraven at yahoo.com writes: What are the recommendations for running KVM images on BTRFS systems using kernel 3.4? I saw older posts on the web complaining about poor performance, but I know a lot of work has gone into btrfs since then.