Re: Pre-allocation of shared memory ... - Mailing list pgsql-hackers

From Jon Lapham
Subject Re: Pre-allocation of shared memory ...
Date
Msg-id 3EE88A97.1010304@extracta.com.br
Whole thread Raw
In response to Re: Pre-allocation of shared memory ...  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Pre-allocation of shared memory ...  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:
> Is this a Linux machine?  If so, the true explanation is probably (c):
> the kernel is kill 9'ing randomly-chosen database processes whenever
> it starts to feel low on memory.  I would suggest checking the
> postmaster log to determine the signal number the failed backends are
> dying with.  The client-side message does not give nearly enough info
> to debug such problems.
> 
> AFAIK the only good way around this problem is to use another OS with a
> more rational design for handling low-memory situations.  No other Unix
> does anything remotely as brain-dead as what Linux does.  Or bug your
> favorite Linux kernel hacker to fix the kernel.

Tom-

Just curious.  What would a rationally designed OS do in an out of 
memory situation?

It seems like from the discussions I've read about the subject there 
really is no rational solution to this irrational problem.

Some solutions such as "suspend process, write image to file" and 
"increase swap space" assume available disk space, which is obviously 
not guaranteed to be avaliable.

-- 
-**-*-*---*-*---*-*---*-----*-*-----*---*-*---*-----*-----*-*-----*--- Jon Lapham  <lapham@extracta.com.br>
Riode Janeiro, Brasil Work: Extracta Moléculas Naturais SA     http://www.extracta.com.br/ Web: http://www.jandr.org/
 
***-*--*----*-------*------------*--------------------*---------------




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