Re: out of memory woes

Tom Lane wrote:
> OK, I played around with this for a bit, and what I find is that in 8.1,
> that SPIExec context is where the sort operation run by CLUSTER's
> reindexing step allocates memory.
Interesting. I wonder if dropping indexes could alleviate this problem.
Please see another recent post of mine for context -
http://groups.google.com/group/pgsql.general/browse_thread/thread/26333d69d7a311ed/39fcfa7ca91771ba?lnk=gst&q=index+angva&rnum=2
The indexes (except for the cluster indexes obviously) should be
dropped and recreated later anyway.

> I don't know why it sometimes fails and sometimes not ---
> maybe you are reaching the swap-space limits of
> the machine when you do several of these in parallel?
The funny thing is that once it does fail, it fails consistently until
the server is bounced - I must have run the cluster script 10 times
after the initial failure. The server's 6g of RAM is normally more than
enough (so normally, maintenance_work_mem is not too high) until this
strange wall is hit. Another funny thing is that according to top, no
more than about 700k of swap is ever used - even when the problem
occurs - and the limit is 2g.

Thanks a lot,
Mark