[ADMIN]openvz and shared memory trouble

Hi,

I have a problem with postgres in combination with openvz.
My hot standby crashes on me when i give it a normal value for
shared_buffers (4GB, which 25% of the memory in the container).
When i tune down the shared_buffers, it works again. But of course this is
far from desireable.

Now, i've seen a couple more messages around the net about openVZ and
postgres that weren't very encouraging:

http://www.postgresql.org/message-id/CAHyXU0xa5EgvjeH=4vp-eZDJdS5kMQuiDivvTRLjY-uZ62Y44w@mail.gmail.com
http://www.postgresql.org/message-id/23206.1254683408@sss.pgh.pa.us
http://postgresql.1045698.n5.nabble.com/BUG-9721-Fatal-error-on-startup-no-free-slots-in-PMChildFlags-array-td5797390.html

But i am in a position where we already have a pretty strong binding with
openVZ.
I also have a colleague that has been using openVZ and postgres on
production for quite a while now, without any problems. And already 1 of
our servers is running a production database in openVZ that is well used,
without any trouble of this kind.

Now, what i would like to know is:

- is there clarity about what the issues are at all
- is it just 1 problem (in openVZ) that make openVZ and postgres so
poorly compatible?
- how can i stay out of trouble (when using postgres inside openVZ)
- who else has trouble with openVZ in combination with postgres, and
what constitutes the trouble?

regards,

WBL

--
"Quality comes from focus and clarity of purpose" -- Mark Shuttleworth