On 2 Sep 2015, at 09:22, Pasi K?rkk?inen <pasik at iki.fi> wrote:
> On Tue, Sep 01, 2015 at 06:47:18AM +0200, Christoph wrote:
>> Hi All
>> 
> 
> Hello,
> 
>> it is possible to tune dom0/domU for better IO/network performance?
>> Since I have changed to Cenots7 dom0, I have a really poor IO
>> performance inside a PV VM.
>> 
>> I have already done what is described on
>> http://wiki.xenproject.org/wiki/Tuning_Xen_for_Performance
>> It is better now but still significantly worse than with centos6 dom0
>> 
>> my settings:
>> 
>> xen parameter: dom0_mem=1024M cpufreq=xen dom0_max_vcpus=2
>> dom0_vcpus_pin
>> 
>> xl sched-credit
>> Cpupool Pool-0: tslice=30ms ratelimit=1000us
>> Name                                ID Weight  Cap
>> Domain-0                             0   1024    0
>> samael                               1    256    0
>> satan                                2    512    0
>> amon                                 3    256    0
>> leviathan                            4    512    0
>> 
>> echo 1048576 > /proc/sys/net/ipv4/tcp_limit_output_bytes on dom0
>> 
>> the both domU's satan and leviathan are very IO performance
oriented
>> (NFS server and downloading vm)
>> 
>> Is there something more what I can do or try?
>> 
>> could it be a selinux issue? I have it in permissive mode there, not
>> disabled. But permissive means only to collect the info not enforcing
>> the rules...
>> 
>> (I use the xen45 pkgs)
>> 
> 
> You forgot to mention the most important thing.. what kind of performance
numbers are you seeing? What are you expecting?
> 
> 
> Thanks,
> 
> ?
> Pasi
Here?s a useful disk i/o stress test program that I got good results with on
openSUSE 13.1, by running it on several VM?s overnight:
Using Bonnie++ for filesystem performance benchmarking
http://archive09.linux.com/feature/139742
HTH
Keith Roberts