Re: [BUGS] problem creating index in 6,5,3 - Mailing list pgsql-bugs

From Tom Lane
Subject Re: [BUGS] problem creating index in 6,5,3
Date
Msg-id 14732.947023218@sss.pgh.pa.us
Whole thread Raw
In response to Re: [BUGS] problem creating index in 6,5,3  (Karl DeBisschop <kdebisschop@range.infoplease.com>)
Responses Re: [BUGS] problem creating index in 6,5,3  (Karl DeBisschop <kdebisschop@range.infoplease.com>)
List pgsql-bugs
Karl DeBisschop <kdebisschop@range.infoplease.com> writes:
> sterno.infoplease.com:/u/kdebisschop> psql -p 5433 webusers -c "CREATE INDEX zdaily_id ON daily (id)"
> pqReadData() -- backend closed the channel unexpectedly.
>         This probably means the backend terminated abnormally
>         before or while processing the request.
> We have lost the connection to the backend, so further processing is impossible.  Terminating.
> [2]+  Done                    psql -p 5433 webusers -c "CREATE INDEX zdaily_date_n ON daily (date,n)"
> sterno.infoplease.com:/u/kdebisschop> psql -p 5433 webusers -c "CREATE INDEX zdaily_id ON daily USING hash (id)"
> ERROR:  cannot open segment 1 of relation zdaily_id
> sterno.infoplease.com:/u/kdebisschop>

> Still no core dump.  Each of these takes an hour or so to croak.

Puzzling...

The lack of a core dump is probably the thing we ought to be paying
attention to here --- most ordinary sorts of unexpected-backend-crash
bugs should dump core.

One possibility is that the kernel is killing that backend process,
most likely for having exceeded a system limit on runtime or disk blocks
written; do you have such limits enabled on your machine?  Or maybe it
is running out of memory/swap space; how big does the process get before
terminating?

Another possibility is that the backend has detected a fatal error
condition and is doing a more-or-less-orderly shutdown.  However if that
were true then there ought to be an error message in the postmaster
logfile; I see no such message in your prior mails.

Also, I just noticed that you are trying to index a "text" field.
How long are the entries in the field?  6.5.* does not have adequate
defenses against overly-long index entries --- the maximum safe size
is 2700 bytes IIRC, but this isn't tested for in the current release.

            regards, tom lane

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