Poor disk IO on Xenserver 6.2

Fri Aug 29 09:21:55 UTC 2014

I have installed FreeBSD 10 release, stable and current on 
Xenserver 6.2 with latest patches. All of them have poor disk 
write speed. Performance from 12MBps - 25MBps. I tried it on
other servers but the performance is the same. Latest Debian
stable on the same machine have 300MBps disk speed. Am I missing
something after installation or this is the default speed?

-- 
Marko Lerota
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