Re: [HACKERS] Parallel pg_restore versus old dump files

2010-06-23 Thread Magnus Hagander
On Wed, Jun 23, 2010 at 03:26, Tom Lane t...@sss.pgh.pa.us wrote: Andrew Dunstan and...@dunslane.net writes: 4. Is there any value in back-porting the Windows FSEEKO support into 8.3 and 8.2?  Arguably, not writing the data offsets is a performance bug.  However a back-port won't do anything

Re: [HACKERS] Parallel pg_restore versus old dump files

2010-06-23 Thread Greg Stark
On Wed, Jun 23, 2010 at 2:26 AM, Tom Lane t...@sss.pgh.pa.us wrote: Uh, that doesn't fix anything: if you can't seek, a TOC at the end of the file is useless.  And the cases where the writer can't seek are likely to be identically the ones where the reader can't seek, viz pg_dump piped to

[HACKERS] Parallel pg_restore versus old dump files

2010-06-22 Thread Tom Lane
I've dug into the problem reported by Igor Neyman: http://archives.postgresql.org/pgsql-admin/2010-06/msg00148.php Unlike previous complainants, Igor was kind enough to supply a pg_dump archive file that triggers the problem. What I find is that his dump file contains no data offsets, ie,

Re: [HACKERS] Parallel pg_restore versus old dump files

2010-06-22 Thread Greg Stark
On Tue, Jun 22, 2010 at 9:07 PM, Tom Lane t...@sss.pgh.pa.us wrote: 3. Perhaps pg_dump ought to emit a warning when it can't seek, instead of just silently not writing the data offsets.  That behavior was okay before when lack of data offsets didn't really matter that much, but lack of data

Re: [HACKERS] Parallel pg_restore versus old dump files

2010-06-22 Thread Andrew Dunstan
Tom Lane wrote: In short, parallel pg_restore is guaranteed to fail on any input file made with a pre-8.4 pg_dump on Windows. It may be that there's some other mechanism involved in the reports we've gotten of parallel restore failing only some of the time, but I'm thinking that the

Re: [HACKERS] Parallel pg_restore versus old dump files

2010-06-22 Thread Tom Lane
Andrew Dunstan and...@dunslane.net writes: Tom Lane wrote: In short, parallel pg_restore is guaranteed to fail on any input file made with a pre-8.4 pg_dump on Windows. IIRC, you can reproduce this on Unix too by sending the output of pg_dump into a pipe. So it's not uniquely a Windows

Re: [HACKERS] Parallel pg_restore versus old dump files

2010-06-22 Thread Andrew Dunstan
Tom Lane wrote: Another possibility is to just remove the inside-the-loop error test altogether: make it just skip till it finds the desired item, and only throw an error if it hits EOF without finding it. In the case that the error test is trying to catch, this would mean significantly more