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On Fri, Feb 15, 2008 at 7:38 AM, Reto Gantenbein |
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<reto.gantenbein@××××××××.ch> wrote: |
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> Hello everybody |
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> |
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> After 3 days messing around I'm at my wits' end. I have two Sun X4200M2 |
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> servers which I would like to setup as Xen dom0s with a drbd-mirrored |
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> file system for paravirtualized domU images. |
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> |
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> I setup an LVM2 on top of DRBD to create the domU volumes and to be able |
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> to backup the domUs with LVM snapshot. |
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> |
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> I was able to configure this setup and make it run, but when accessing |
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> the block-frontend device in domU this is terrible slow. E.g. copying a |
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> 5G file via scp and gigabit Ethernet onto the domU leads to a lot of |
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> stalls during transfer. The peak transfer rate is about 5MB/s every 1-2 |
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> minutes but generally it's about a few hundred KB/s. When copying the |
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> same file onto the DRBD volume mounted directly in dom0 it works with |
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> the expected 30-40MB/s. Another test was to sync the portage tree but |
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> also this takes maybe about 20 minutes or spontaneously raises some |
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> timeout errors. Sometimes after a while the disk fully detaches from the |
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> domU, so every call of a binary in domU leads to a "Input/output error". |
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> I guess the domU kernel adds this troubles, but why? There are no |
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> statements in any log files. E.g. /var/log/xen/xend-debug.log doesn't |
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> notify the detached block device. |
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> |
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> I use Gentoo Linux and tried so far with xen-3.1.2 and xen-3.2.0, |
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> xen-sources-2.6.18-r8, xen-sources-2.6.20-r6 and xen-sources-2.6.22, |
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> drbd-8.0.7, drbd-8.0.8 and drbd-8.0.11. |
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> |
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> The longer the more I expect a general problem with Xen and this setup, |
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> a kernel problem or a misconfiguration. Attached are the most important |
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> configurations for this setup. |
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> |
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> Are there any hints or other experiences for such a setup? All ideas are |
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> welcome. |
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> |
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> Thanks for reading and giving any hints... |
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> Cheers Reto Gantenbein |
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|
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I couldn't quite tell from the above but do you see the bad |
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performance inside domU only when using scp/rsync or is it just as |
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slow when you copy files locally? |
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|
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-- |
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Michael Marineau |
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Oregon State University |
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mike@××××××××.org |
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-- |
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