Re: DOMU Disk I/O

[Roger Pau Monné <roger.pau%citrix.com@localhost>]

On 21/12/12 06:28, Cherry G. Mathew wrote:
> On 10 December 2012 01:09,  <gary%duzan.org@localhost> wrote:
>>    I've been running a NetBSD VPS at prgmr.com for several years
>> now, and generally been pleased. However, recently I've noticed
>> that my disk I/O rates have been rather bad. The upgrade to 6.0_STABLE
>> was rather slow, and I regularly see "systat vm" report xbd0 %busy
>> at 100% with only a handful of transfers and sometimes under 100K
>> bytes. Is this likely to be a problem with the 6.0 DOMU or something
>> on the DOM0? Should I consider going back to 5.2?
>>
> 
> Hi Gary,
> 
> Are you running MP by any chance ? roger@ did some benchmarks and
> there were no significant i/o related performance issues, so I'm
> curious.

I've done some testing in the past, but it was only with big files. If
you are working with a large set of small files you may experience
slowdown. For example decompressing a src.tar.gz snapshot can take
around ~30min, while it takes less than 2 minutes on a Linux DomU (using
the same Dom0). I've reported this on another thread, but I haven't had
time to debug this any further
(http://mail-index.netbsd.org/tech-kern/2012/10/29/msg014249.html). Do
you know by any change the Dom0 OS and kernel version?