Looking for some advice on write speed. I currently have my domU''s installed to 8GB files on a GFS file system. When I create these domU''s and try to write to them the speed is horrible something that should take 10 seconds takes about 2 minutes. Is there any way to speed up the write speed for this configuration? Here is what my .cfg file looks like. name = "aws_u01" memory = "256" disk = [ ''tap:aio:/mnt/domU-storage/aws-u01,xvda,w'', ] vif = [ ''mac=00:16:3e:4e:b6:53, bridge=xenbr0'', ] vfb = ["type=vnc,vncunused=1"] uuid = "ab8e67d9-7375-cb79-e35c-8ebfca130f8b" bootloader="/usr/bin/pygrub" vcpus=1 on_reboot = ''restart'' on_crash = ''restart'' _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Thu, Jun 21, 2007 at 10:55:23AM -0500, James Wilson wrote:> Looking for some advice on write speed. I currently have my domU''s > installed to 8GB files on a GFS file system. When I create these domU''s > and try to write to them the speed is horrible something that should > take 10 seconds takes about 2 minutes. Is there any way to speed up the > write speed for this configuration? Here is what my .cfg file looks like.Are the files for your disk sparse, or fully-allocated ? If they are sparse, then you should re-create them as fully pre-allocated. Whenever a sparse disk has to be extended to allocate further blocks performance is horrific. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=| _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
The space is fully allocated. Daniel P. Berrange wrote:> On Thu, Jun 21, 2007 at 10:55:23AM -0500, James Wilson wrote: > >> Looking for some advice on write speed. I currently have my domU''s >> installed to 8GB files on a GFS file system. When I create these domU''s >> and try to write to them the speed is horrible something that should >> take 10 seconds takes about 2 minutes. Is there any way to speed up the >> write speed for this configuration? Here is what my .cfg file looks like. >> > > Are the files for your disk sparse, or fully-allocated ? If they are > sparse, then you should re-create them as fully pre-allocated. Whenever > a sparse disk has to be extended to allocate further blocks performance > is horrific. > > Dan. >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
James Wilson wrote:> Looking for some advice on write speed. I currently have my domU''s > installed to 8GB files on a GFS file system. When I create these > domU''s and try to write to them the speed is horrible something that > should take 10 seconds takes about 2 minutes. Is there any way to > speed up the write speed for this configuration? Here is what my .cfg > file looks like. >If you can at all arrange it give dom0 its own CPU - even if that means making all the domUs single threaded. It makes a massive difference to throughput. domU performance never seems to reach dom0 speeds, but it''s acceptable enough... loopback performance is the best (but that''s caching in memory on dom0 so what you gain in speed you lose in potential integrity if there''s a hardware crash). lvm performance varies between 10% and 50% of native in my experience. I''ve never been able to do anything about network performance though.. topping about at about 5mb/sec. If that''s important to you use a dedicated machine or vmware (possibly xen commercial, which may have optimised network drivers). Tony _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Tony Hoyle wrote:> I''ve never been able to do anything about network performance though.. > topping about at about 5mb/sec. If that''s important to you use a > dedicated machine or vmware (possibly xen commercial, which may have > optimised network drivers).Apparently novell have some: http://www.virtualization.info/2007/06/novell-to-offer-guest-os-optimized.html Rather pricy, but if you''re wedded to a xen solution may be the answer. Tony _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thanks for the help. I will look into your suggetions. Tony Hoyle wrote:> Tony Hoyle wrote: >> I''ve never been able to do anything about network performance >> though.. topping about at about 5mb/sec. If that''s important to you >> use a dedicated machine or vmware (possibly xen commercial, which may >> have optimised network drivers). > > Apparently novell have some: > > http://www.virtualization.info/2007/06/novell-to-offer-guest-os-optimized.html > > > Rather pricy, but if you''re wedded to a xen solution may be the answer. > > Tony > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users