Re: [HACKERS] Getting to 9.3 beta

2013-03-30 Thread Alexander Korotkov
On Fri, Mar 29, 2013 at 7:22 PM, Andres Freund and...@2ndquadrant.comwrote: - Index based regexp search for pg_trgm: Seems like the patch is undergoing restructuring of the regex access API = move to next fest Last proposal of regex API by Tom seems simple enough in implementation for

Re: [HACKERS] Cube extension improvement, GSoC

2013-03-30 Thread Alexander Korotkov
Hi, Jey! I remember I've started couple of threads related to cube extension: http://www.postgresql.org/message-id/4f30616d.3030...@gmail.com http://www.postgresql.org/message-id/4f3c16e9.90...@gmail.com Could you provide some feedback to GSoC proposal of Stas? On Sat, Mar 23, 2013 at 3:10 AM,

[HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread 赖文豫
As we know, SSDs are widely used in various kinds of applications. But the SMGR in PostgreSQL still only support magnetic disk. How do we make full use of SSDs to improve the performance of PostgreSQL? -- Just do it!

Re: [HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread Bruce Momjian
On Sat, Mar 30, 2013 at 10:08:44PM +0800, 赖文豫 wrote: As we know, SSDs are widely used in various kinds of applications. But the SMGR in PostgreSQL still only support magnetic disk. How do we make full use of SSDs to improve the performance of PostgreSQL? When the storage manager (SMGR)

Re: [HACKERS] Cube extension improvement, GSoC

2013-03-30 Thread Alexander Korotkov
On Sat, Mar 30, 2013 at 3:55 PM, Alexander Korotkov aekorot...@gmail.comwrote: Hi, Jey! I remember I've started couple of threads related to cube extension: Oh, it's a typo. I remember you've started those threads. http://www.postgresql.org/message-id/4f30616d.3030...@gmail.com

Re: [HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread Tom Lane
Bruce Momjian br...@momjian.us writes: On Sat, Mar 30, 2013 at 10:08:44PM +0800, 赖文豫 wrote: As we know, SSDs are widely used in various kinds of applications. But the SMGR in PostgreSQL still only support magnetic disk. How do we make full use of SSDs to improve the performance of

Re: [HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread Andrew Dunstan
On 03/30/2013 12:28 PM, Tom Lane wrote: Bruce Momjian br...@momjian.us writes: On Sat, Mar 30, 2013 at 10:08:44PM +0800, 赖文豫 wrote: As we know, SSDs are widely used in various kinds of applications. But the SMGR in PostgreSQL still only support magnetic disk. How do we make full use of

Re: [HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread Tom Lane
Andrew Dunstan and...@dunslane.net writes: This isn't the first time I've seen this sort of comment. Do we need to add some wording like the above to the top of md.c and the README in that directory? Yeah, probably. I'll go write something ... regards, tom lane --

Re: [HACKERS] Fix for pg_upgrade and invalid indexes

2013-03-30 Thread Andres Freund
On 2013-03-29 19:03:05 -0400, Tom Lane wrote: Andres Freund and...@2ndquadrant.com writes: Those columns cannot be NULL, so using IS DISTINCT FROM seems a bit clumsy. That was what I started to write, too, but actually I think the IS DISTINCT is correct and the RIGHT JOIN should be a LEFT

Re: [HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread Satoshi Nagayasu
2013/03/30 23:31, Bruce Momjian wrote: On Sat, Mar 30, 2013 at 10:08:44PM +0800, 赖文豫 wrote: As we know, SSDs are widely used in various kinds of applications. But the SMGR in PostgreSQL still only support magnetic disk. How do we make full use of SSDs to improve the performance of PostgreSQL?

[HACKERS] HS and clog

2013-03-30 Thread Andres Freund
Hi, During the investigation of http://archives.postgresql.org/message-id/CAL_0b1t%3DWuM6roO8dki%3Dw8DhH8P8whhohbPjReymmQUrOcNT2A%40mail.gmail.com I noticed that during HS we do the following in RecordKnownAssignedTransactionIds: if (TransactionIdFollows(xid, latestObservedXid))

Re: [HACKERS] Hash Join cost estimates

2013-03-30 Thread Stephen Frost
Jeff, * Jeff Davis (pg...@j-davis.com) wrote: On Thu, 2013-03-28 at 19:56 -0400, Stephen Frost wrote: 41K hashed, seqscan 4M: 115030.10 + 1229.46 = 116259.56 4M hashed, seqscan 41K: 1229.46 + 211156.20 = 212385.66 I think those are backwards -- typo? Yes, sorry, those are backwards.

Re: [HACKERS] Hash Join cost estimates

2013-03-30 Thread Stephen Frost
* Tom Lane (t...@sss.pgh.pa.us) wrote: I think the point is that there may *not* be few hash collisions ... Right, but that's actually all entirely based on concerns over there being duplicates (hence why we consider the MCVs and ndistinct), which makes *some* sense given that we currently have

Re: [HACKERS] Hash Join cost estimates

2013-03-30 Thread Stephen Frost
* Jeff Davis (pg...@j-davis.com) wrote: In Stephen's case the table was only 41KB, so something still seems off. Maybe we should model the likelihood of a collision based on the cardinalities (assuming a reasonably good hash function)? It's not really 'hash collisions' that we're trying to be

Re: [HACKERS] Changing recovery.conf parameters into GUCs

2013-03-30 Thread Josh Berkus
Simon, All, The new approach seems fine to me; I haven't looked at the code. If Tom doesn't feel like it's overly complicated, then this seems like a good compromise. The desire to move recovery.conf/trigger to a different directory is definitely wanted by our Debian contingent. Right now, the

Re: [HACKERS] HS and clog

2013-03-30 Thread Simon Riggs
On 30 March 2013 18:20, Andres Freund and...@2ndquadrant.com wrote: Simon, do you remember why you added that? That doesn't look like code I added, but I'll look some more. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training Services

Re: [HACKERS] Changing recovery.conf parameters into GUCs

2013-03-30 Thread Tom Lane
Josh Berkus j...@agliodbs.com writes: The desire to move recovery.conf/trigger to a different directory is definitely wanted by our Debian contingent. Right now, the fact that Debian has all .confs in /etc/, but that it doesn't work to relocate recovery.conf, is a constant source of

Re: [HACKERS] HS and clog

2013-03-30 Thread Simon Riggs
On 30 March 2013 18:20, Andres Freund and...@2ndquadrant.com wrote: Imo this shouldn't be needed. In principle, I think your premise looks correct. ExtendCLOG() is not needed. If the xid truly is known assigned at a point in time, then the clog should already have been extended to allow that.

Re: [HACKERS] HS and clog

2013-03-30 Thread Tom Lane
Simon Riggs si...@2ndquadrant.com writes: On 30 March 2013 18:20, Andres Freund and...@2ndquadrant.com wrote: Imo this shouldn't be needed. In principle, I think your premise looks correct. ExtendCLOG() is not needed. If the xid truly is known assigned at a point in time, then the clog

Re: [HACKERS] HS and clog

2013-03-30 Thread Andres Freund
On 2013-03-30 18:24:44 -0400, Tom Lane wrote: Simon Riggs si...@2ndquadrant.com writes: On 30 March 2013 18:20, Andres Freund and...@2ndquadrant.com wrote: Imo this shouldn't be needed. In principle, I think your premise looks correct. ExtendCLOG() is not needed. If the xid truly

Re: [HACKERS] HS and clog

2013-03-30 Thread Andres Freund
On 2013-03-30 23:58:26 +0100, Andres Freund wrote: I am pretty sure that the scenario you describe happens for SUBTRANS tho. Leading to the reported bug. For a slightly too long explanation see: http://archives.postgresql.org/message-id/20130330172144.GI28736%40alap2.anarazel.de Greetings,

Re: [HACKERS] By now, why PostgreSQL 9.2 don't support SSDs?

2013-03-30 Thread Ants Aasma
On Mar 30, 2013 7:13 PM, Satoshi Nagayasu sn...@uptime.jp wrote: But I heard that larger block size, like 256kB, would take advantage of the SSD performance because of the block management within SSD. This is only true for very bad SSDs. Any SSD that you would want to trust with your data do

Re: [HACKERS] Fix for pg_upgrade and invalid indexes

2013-03-30 Thread Bruce Momjian
OK, patch applied and backpatched as far back as pg_upgrade exists in git. --- On Fri, Mar 29, 2013 at 11:35:13PM -0400, Bruce Momjian wrote: On Fri, Mar 29, 2013 at 07:03:05PM -0400, Tom Lane wrote: Andres Freund

Re: [HACKERS] pkg-config files for libpq and ecpg

2013-03-30 Thread Peter Eisentraut
On Wed, 2013-03-27 at 17:06 -0400, Tom Lane wrote: Peter Eisentraut pete...@gmx.net writes: On 3/24/13 1:55 PM, Tom Lane wrote: I experimented a bit with this version of the patch. The hunk that removes -I$(libpq_srcdir) and $(libpq) from the ecpg/compatlib build breaks the build for me,

Re: [HACKERS] citext like searches using index

2013-03-30 Thread David E. Wheeler
On Mar 20, 2013, at 1:45 AM, David E. Wheeler da...@kineticode.com wrote: Is there currently any way to create an index that can be used to speed up searches like the one above? If not, do you have any idea how it might be implemented? Perhaps I could give it a try myself. Thank you in

Re: [HACKERS] citext like searches using index

2013-03-30 Thread Tom Lane
David E. Wheeler da...@kineticode.com writes: Hackers, what would be required to get an index on a CITEXT column to support LIKE? The LIKE index optimization is hard-wired into match_special_index_operator(), which never heard of citext's ~~ operators. I've wanted for years to replace that