Re: pg_terminate_backend() issues - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: pg_terminate_backend() issues
Date
Msg-id 200804172058.m3HKwA421845@momjian.us
Whole thread Raw
In response to Re: pg_terminate_backend() issues  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> > Tom Lane wrote:
> >> The closest thing I can think of to an automated test is to run repeated
> >> sets of the parallel regression tests, and each time SIGTERM a randomly
> >> chosen backend at a randomly chosen time.  Then see if anything "funny"
> 
> > Yep, that was my plan, plus running the parallel regression tests you
> > get the possibility of >2 backends.
> 
> I was intentionally suggesting only one kill per test cycle.  Multiple
> kills will probably create an O(N^2) explosion in the set of possible
> downstream-failure deltas.  I doubt you'd really get any improvement
> in testing coverage to justify the much larger amount of hand validation
> needed.
> 
> It also strikes me that you could make some simple alterations to the
> regression tests to reduce the set of observable downstream deltas.
> For example, anyplace where a test loads a table with successive INSERTs
> and that table is used by later tests, wrap the INSERT sequence with
> BEGIN/END.  Then there is only one possible downstream delta (empty
> table) and not N different possibilities for an N-row table.

I have added pg_terminate_backend() to use SIGTERM and will start
running tests as discussed with Tom.  I will post my scripts too.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +


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