[Picking up on this old thread]
Question for those of you running OpenBSD HVM DomUs, does your IO
performance suck?
Description:
I have OpenBSD 4.3 DomU running HVM mode with 1x vcpu on top on
OpenSolaris b97 xVM Dom0, which pins down 2x vcpus (box is a quad-core
1.9GHz opteron with 8GB mem). Like John (below), I also pass
"model=ne2k_pci" as part of the vif. The system is reasonably
responsive over console when not doing any IO, especially disk, when the
performance tanks. To put this in perspective, when I was installing
OpenBSD, it took 30+ mins for it to install the packages and thats not
including any of the X packages! Likewise, a simple file-copy test gave
me these results:
Copy large file from Desktop to Dom (using `scp`) :
Dom0: ~27136KB/s (opensolaris b97)
DomU: ~322KB/s (openbsd 4.3, hvm)
Copy large file from Dom to Desktop (using `scp`):
Dom0: ~28441KB/s (opensolaris b97)
DomU: ~662KB/s (openbsd 4.3, hvm)
Finally, running `bonnie++` on the Dom0 in DomU gives:
_*Bonnie++ on Dom0*_
Version 1.03d ------ Sequential Output ------ --- Sequential
Input --- --Random-
-Per Char- --Block-- -Rewrite- --Per Char--
--Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP
K/sec %CP K/sec %CP
san 8G 67051 85 166574 59 126454 63 71058 96
362940 76 1645 11
------ Sequential Create ------ -------- Random
Create --------
-Create-- --Read--- -Delete-- -Create--
--Read--- -Delete--
files K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec
%CP K/sec %CP
16 15815 99 +++++ +++ 22903 99 15222 99 +++++
+++ 22339 99
_*Bonnie++ in zvol-backed DomU (openbsd 4.3, hvm)*_
Version 1.03 ------ Sequential Output ------ --- Sequential
Input --- --Random-
-Per Char- --Block-- -Rewrite- --Per Char--
--Block-- --Seeks--
Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP
K/sec %CP K/sec %CP
puffy 300M 451 0 295 0 184 0 976 4
1521 2 26.8 1
------ Sequential Create ------ -------- Random
Create --------
-Create-- --Read--- -Delete-- -Create--
--Read--- -Delete--
files K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec
%CP K/sec %CP
16 8 1 +++++ +++ 16 1 8 1 +++++
+++ 10 0
I have already posted these results to the xVM mailing list and they
said that they have never seen the HVM performance this bad before
(where 30Mb/s is the norm) and also offered:
If this was just disk or net then I'd suspect that the device
emulation simply didn't match up well with the OpenBSD driver, but
given that you're seeing both as slow it may well be a broader
problem.
BTW, my networking performance is also not great - its about ~7 Mb/s -
over GE interfaces using Cat5e. This is also slow as running the same
`iperf` test when openbsd is on the bare-metal gives ~534 Mb/s. Just
the same, 7 Mb/s is way faster than my disk I/O (~0.5 Mb/s avg).
So, for those of you running OpenBSD HVM DomUs, does your IO
performance suck this bad too?
Thanks,
Kent
John Jackson wrote:
> OpenBSD as DomU works using hardware virtualization for me. There's
> the occasional lockup that I haven't looked into too much. You can
> launch vncviewer to get a console. My working config is at the bottom.
>
> John
>
> On Wed, Feb 06, 2008 at 11:55:05PM +0100, Julien Cabillot wrote:
>
>> It's work but I had really bad performances with the network (timeout on
>> the interface re).
>> Dmesg: http://www.openbsd-france.org/ml/archives/msg02494.html
>>
>>
>
> I found that setting the vif interface to 'model=ne2k_pci' helps with
> the timeouts.
>
>
>> On jeu, 2008-02-07 at 00:29 +0200, NetOne - Doichin Dokov wrote:
>>
>>> I'm looking to replace a Linux domU with a BSD one, preferably OpenBSD.
>>> Anyone any success running stable OpenBSD (FreeBSD would also suffice)
>>> as domU in a Xen system? If so, willing to share config / how-to /
>>> experience?
>>>
>>> Kind regards,
>>> Doichin
>>>
>
> Here's a working Xen config:
> =================================================================
> import os, re
> arch = os.uname()[4]
> if re.search('64', arch):
> arch_libdir = 'lib64'
> else:
> arch_libdir = 'lib'
> kernel = "/usr/lib/xen/boot/hvmloader"
> builder='hvm'
> memory = 256
> name = "obsd"
> pae=0
> vif = [ 'type=ioemu, mac=00:16:3e:7d:be:ef, model=ne2k_pci' ]
> disk = [
> 'file:/disk/homer.disk,hda,w','file:/disk/obsd42_amd64.iso,ioemu:hdc:cdrom,r'
> ]
> device_model = '/usr/' + arch_libdir + '/xen/bin/qemu-dm'
> boot='cd'
> sdl=0
> vnc=1
> vncviewer=0
> nographic=0
> stdvga=0
> serial='pty'
> ne2000=1
> audio=0
> localtime=1
> =================================================================
