vmdaemon CPU usage and poor performance in 10.0-RELEASE

[Ronald Klop]

On Wed, 13 Aug 2014 17:42:37 +0200, Polyack, Steve  
<Steve.Polyack at intermedix.com> wrote:

>
>> -----Original Message-----
>> From: Kurt Jaeger [mailto:lists at opsec.eu]
>> Sent: Wednesday, August 13, 2014 11:25 AM
>>
>> Hi!
>>
>> > We have a handful of database servers running FreeBSD 10.0-RELEASE
>> > and PostgreSQL 9.3.4.  The servers have 128GB or 256GB of RAM.
>>
>> Are you aware of the recent work on that topic ?
>>
>> https://www.freebsd.org/news/status/report-2014-04-2014-
>> 06.html#PostgreSQL-Performance-Improvements
>>
>> Maybe kib@ knows more about this ?
>>
>
> I've recently read over this and some other posts, but they all seem to  
> center around poor postgres performance.  In our case at least, some  
> light to medium usage of postgres generally makes the entire system  
> unusable.
>
> The patches & documents linked there also all seem to be for -CURRENT,  
> which we aren't running.  We're not too keen on the idea of using  
> CURRENT in production, either.  We're planning on testing 10-STABLE, but  
> I was just hoping to gain some insight into what the problem may be and  
> whether recent commits to vmdaemon code in the -STABLE tree may have a  
> positive effect on what we've seen.
>
> Steve

It looks like a fix mentioned in part 2.1 in the pdf  
(https://www.kib.kiev.ua/kib/pgsql_perf_v2.0.pdf, from the status report)  
was only just committed to 11-CURRENT.
http://svnweb.freebsd.org/changeset/base/270011

I guess it is advisable to stay on pgsql 9.2.x until these improvements  
are MFC'ed to 10-STABLE.

Regards,
Ronald.