Re: [HACKERS] Page Checksums

2011-12-28 Thread Robert Haas
On Tue, Dec 27, 2011 at 1:39 PM, Jeff Davis pg...@j-davis.com wrote: On Mon, 2011-12-19 at 07:50 -0500, Robert Haas wrote: I think it would be regrettable if everyone had to give up 4 bytes per page because some people want checksums. I can understand that some people might not want the CPU

Re: [HACKERS] 16-bit page checksums for 9.2

2011-12-28 Thread Simon Riggs
On Wed, Dec 28, 2011 at 7:42 AM, Heikki Linnakangas heikki.linnakan...@enterprisedb.com wrote: How would you know when to look in the double write buffer? You scan the double-write buffer, and every page in the double write buffer that has a valid checksum, you copy to the main storage.

Re: [HACKERS] Page Checksums

2011-12-28 Thread Simon Riggs
On Wed, Dec 28, 2011 at 9:00 AM, Robert Haas robertmh...@gmail.com wrote:  What I'm not too clear about is whether a 16-bit checksum meets the needs of people who want checksums. We need this now, hence the gymnastics to get it into this release. 16-bits of checksum is way better than zero

Re: [HACKERS] Pause at end of recovery

2011-12-28 Thread Simon Riggs
On Thu, Dec 22, 2011 at 6:16 AM, Simon Riggs si...@2ndquadrant.com wrote: I can see a reason to do this now. I've written patch and will commit on Friday. Nudge me if I don't. It's hard to write this so it works in all cases and doesn't work in the right cases also. Basically, we can't get in

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Tatsuo Ishii
/index_en.php Japanese: http://www.sraoss.co.jp inline: PostgreSQL-ppc-TAS_SPIN-20111228.png ppc-TAS_SPIN-20111228.diff.gz Description: Binary data -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql

Re: [HACKERS] pgstat wait timeout

2011-12-28 Thread Alvaro Herrera
Excerpts from Steve Crawford's message of mar dic 27 22:51:06 -0300 2011: I have a system (9.0.4 on Ubuntu Server 10.04 LTS x86_64) that is currently in test/dev mode. I'm currently seeing the following messages occurring every few seconds: ... Dec 27 17:43:22 foo postgres[23693]: [6-1]

[HACKERS] ordering op for WHERE

2011-12-28 Thread YAMAMOTO Takashi
hi, does it make sense to teach the planner (and the executor?) use an ordering op to optimize queries like the following? select * from t where a - 1000 10 YAMAMOTO Takashi -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription:

Re: [HACKERS] Review of VS 2010 support patches

2011-12-28 Thread Andrew Dunstan
On 12/27/2011 11:09 PM, Brar Piening wrote: Brar Piening wrote: I have to admit that it's currently broken (it builds but fails during regression tests becuse it can't connect) when building with Visual Studio 2010 or Windows SDK 7.1 because of commit

Re: [HACKERS] Review of VS 2010 support patches

2011-12-28 Thread Magnus Hagander
On Wed, Dec 28, 2011 at 14:38, Andrew Dunstan and...@dunslane.net wrote: On 12/27/2011 11:09 PM, Brar Piening wrote: Brar Piening wrote: I have to admit that it's currently broken (it builds but fails during regression tests becuse it can't connect) when building with Visual Studio 2010

Re: [HACKERS] Review of VS 2010 support patches

2011-12-28 Thread Andrew Dunstan
On 12/28/2011 08:43 AM, Magnus Hagander wrote: On Wed, Dec 28, 2011 at 14:38, Andrew Dunstanand...@dunslane.net wrote: On 12/27/2011 11:09 PM, Brar Piening wrote: Brar Piening wrote: I have to admit that it's currently broken (it builds but fails during regression tests becuse it can't

Re: [HACKERS] Review of VS 2010 support patches

2011-12-28 Thread Magnus Hagander
On Wed, Dec 28, 2011 at 15:08, Andrew Dunstan and...@dunslane.net wrote: On 12/28/2011 08:43 AM, Magnus Hagander wrote: On Wed, Dec 28, 2011 at 14:38, Andrew Dunstanand...@dunslane.net  wrote: On 12/27/2011 11:09 PM, Brar Piening wrote: Brar Piening wrote: I have to admit that it's

Re: [HACKERS] Page Checksums + Double Writes

2011-12-28 Thread Greg Stark
On Tue, Dec 27, 2011 at 10:43 PM, Merlin Moncure mmonc...@gmail.com wrote: I bet if you kept a judicious number of clog pages in each local process with some smart invalidation you could cover enough cases that scribbling the bits down would become unnecessary. I don't understand how any

Re: [HACKERS] Page Checksums + Double Writes

2011-12-28 Thread Merlin Moncure
On Wed, Dec 28, 2011 at 8:45 AM, Greg Stark st...@mit.edu wrote: On Tue, Dec 27, 2011 at 10:43 PM, Merlin Moncure mmonc...@gmail.com wrote:  I bet if you kept a judicious number of clog pages in each local process with some smart invalidation you could cover enough cases that scribbling the

Re: [HACKERS] pgstat wait timeout

2011-12-28 Thread Steve Crawford
On 12/28/2011 05:05 AM, Alvaro Herrera wrote: Excerpts from Steve Crawford's message of mar dic 27 22:51:06 -0300 2011: I have a system (9.0.4 on Ubuntu Server 10.04 LTS x86_64) that is currently in test/dev mode. I'm currently seeing the following messages occurring every few seconds: ... Dec

Re: [HACKERS] Page Checksums

2011-12-28 Thread Heikki Linnakangas
On 28.12.2011 11:00, Robert Haas wrote: Admittedly, most of the fat is probably in the tuple header rather than the page header, but at any rate I don't consider burning up 1% of our available storage space to be a negligible overhead. 8 / 8192 = 0.1%. -- Heikki Linnakangas EnterpriseDB

Re: [HACKERS] pgstat wait timeout

2011-12-28 Thread Alvaro Herrera
Excerpts from Steve Crawford's message of mié dic 28 13:24:37 -0300 2011: On 12/28/2011 05:05 AM, Alvaro Herrera wrote: Excerpts from Steve Crawford's message of mar dic 27 22:51:06 -0300 2011: I have a system (9.0.4 on Ubuntu Server 10.04 LTS x86_64) that is currently in test/dev mode.

Re: [HACKERS] 16-bit page checksums for 9.2

2011-12-28 Thread Heikki Linnakangas
On 28.12.2011 11:22, Simon Riggs wrote: On Wed, Dec 28, 2011 at 7:42 AM, Heikki Linnakangas heikki.linnakan...@enterprisedb.com wrote: How would you know when to look in the double write buffer? You scan the double-write buffer, and every page in the double write buffer that has a valid

[HACKERS] age(xid) on hot standby

2011-12-28 Thread Peter Eisentraut
The check_postgres txn_wraparound action[0] runs this query: SELECT datname, age(datfrozenxid) AS age FROM pg_database WHERE datallowconn ORDER BY 1, 2 On a hot standby, this fails with: ERROR: cannot assign TransactionIds during recovery So, a couple of things to wonder about: Is it

Re: [HACKERS] pgstat wait timeout

2011-12-28 Thread Steve Crawford
On 12/28/2011 09:34 AM, Alvaro Herrera wrote: Excerpts from Steve Crawford's message of mié dic 28 13:24:37 -0300 2011: On 12/28/2011 05:05 AM, Alvaro Herrera wrote: Excerpts from Steve Crawford's message of mar dic 27 22:51:06 -0300 2011: I have a system (9.0.4 on Ubuntu Server 10.04 LTS

Re: [HACKERS] contrib/README

2011-12-28 Thread Dimitri Fontaine
Tom Lane t...@sss.pgh.pa.us writes: I wonder whether it's time to drop that file altogether ... it served a purpose back before we integrated contrib into the SGML docs, but now I'm not quite sure why we should bother with it. I wonder if we shouldn't keep the file and have it just point to

Re: [HACKERS] age(xid) on hot standby

2011-12-28 Thread Alvaro Herrera
Excerpts from Peter Eisentraut's message of mié dic 28 15:04:09 -0300 2011: The check_postgres txn_wraparound action[0] runs this query: SELECT datname, age(datfrozenxid) AS age FROM pg_database WHERE datallowconn ORDER BY 1, 2 On a hot standby, this fails with: ERROR: cannot

Re: [HACKERS] age(xid) on hot standby

2011-12-28 Thread Tom Lane
Alvaro Herrera alvhe...@commandprompt.com writes: Excerpts from Peter Eisentraut's message of mié dic 28 15:04:09 -0300 2011: On a hot standby, this fails with: ERROR: cannot assign TransactionIds during recovery I think we could just have the xid_age call GetCurrentTransactionIdIfAny, and

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Heikki Linnakangas
On 28.12.2011 14:03, Tatsuo Ishii wrote: With help from IBM Japan Ltd. we did some tests on a larger IBM machine than Tom Lane has used for his test(http://archives.postgresql.org/message-id/8292.1314641...@sss.pgh.pa.us). In his case it was IBM 8406-71Y, which has 8 physical cores and 4SMT(32

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Tatsuo Ishii
On 28.12.2011 14:03, Tatsuo Ishii wrote: With help from IBM Japan Ltd. we did some tests on a larger IBM machine than Tom Lane has used for his test(http://archives.postgresql.org/message-id/8292.1314641...@sss.pgh.pa.us). In his case it was IBM 8406-71Y, which has 8 physical cores and

Re: [HACKERS] Review of VS 2010 support patches

2011-12-28 Thread Brar Piening
Andrew Dunstan wrote: Can you narrow down exactly what in that commit broke VS 2010? Are there any compiler warnings? I was able to nail down the problem. Running the regression tests (vcregress check) gives the following messages: snip == creating temporary installation

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Tom Lane
Heikki Linnakangas heikki.linnakan...@enterprisedb.com writes: config/c-compiler.m4 doesn't seem like the right place for the configure test. Would there be any harm in setting the lwarx hint always; what would happen on older ppc processors that don't support it? More to the point, a

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Kevin Grittner
Tom Lane wrote: a configure test only proves whether the build machine can deal with the flag, not whether the machine the executables will ultimately run on knows what the flag means. We cannot assume that the build and execution boxes are the same. (In general, AC_TRY_RUN tests are

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Tatsuo Ishii
OT: Please use mail address manabu@gmail.com, not manabu@gmailc.com when following this thread. I accidently made a mistake when I posted the first mail in this thread. -- Tatsuo Ishii SRA OSS, Inc. Japan English: http://www.sraoss.co.jp/index_en.php Japanese: http://www.sraoss.co.jp

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Manabu Ori
2011/12/29 Tatsuo Ishii is...@postgresql.org Impressive results. config/c-compiler.m4 doesn't seem like the right place for the configure test. Would there be any harm in setting the lwarx hint always; what would happen on older ppc processors that don't support it? I think the load

Re: [HACKERS] spinlocks on HP-UX

2011-12-28 Thread Manabu Ori
a configure test only proves whether the build machine can deal with the flag, not whether the machine the executables will ultimately run on knows what the flag means. We cannot assume that the build and execution boxes are the same. (In general, AC_TRY_RUN tests are best avoided