Re: [HACKERS] windows doesn't notice backend death

2009-05-02 Thread Alvaro Herrera
Andrew Dunstan wrote: > Well, I'm not I know how to find out the answer to your question. I > could try attaching a debugger to the postmaster - if I knew where to > put a breakpoint. Did you try reaper()? It's the SIGCHLD handler. -- Alvaro Herrerahttp://ww

Re: [HACKERS] Updated Korean character set mappings

2009-05-02 Thread Tatsuo Ishii
> Here are update map files for our Korean character sets. The changes: > > All character sets updated to add the 3 characters added since 1998: Euro > Sign, Postal Mark, and Registered Mark. > > UHC updated to add a number of new Hanja that have been added over the years. > This brings the

Re: [HACKERS] windows doesn't notice backend death

2009-05-02 Thread Andrew Dunstan
Tom Lane wrote: Andrew Dunstan writes: Tom Lane wrote: Ick. Is it possible that the postmaster did get a report, but thought it was normal session termination? If so, how could we distinguish? If that were the case then it would not have the dead process still listed a

Re: [HACKERS] windows doesn't notice backend death

2009-05-02 Thread Tom Lane
Andrew Dunstan writes: > Tom Lane wrote: >> Ick. Is it possible that the postmaster did get a report, but thought >> it was normal session termination? If so, how could we distinguish? > If that were the case then it would not have the dead process still > listed as a live backend, ISTM, which

Re: [HACKERS] windows doesn't notice backend death

2009-05-02 Thread Andrew Dunstan
Tom Lane wrote: Andrew Dunstan writes: ... I killed a backend using the task manager, and the postmaster never noticed. Ick. Is it possible that the postmaster did get a report, but thought it was normal session termination? If so, how could we distinguish? If that

Re: [HACKERS] windows doesn't notice backend death

2009-05-02 Thread Tom Lane
Andrew Dunstan writes: > ... I killed a backend using the task manager, and > the postmaster never noticed. Ick. Is it possible that the postmaster did get a report, but thought it was normal session termination? If so, how could we distinguish? regards, tom lane --

Re: [HACKERS] Gist consistent and compression

2009-05-02 Thread Dimitri Fontaine
Hi, Le 1 mai 09 à 23:04, Yeb Havinga a écrit : An idea for possible improvement of query speed on gist indexes with a costly compression function. We have a gist index that uses a compressed internal datatype. The compression is with some cost (it involves a syscache lookup). [...] small

Re: [HACKERS] GEQO: ERX

2009-05-02 Thread Dimitri Fontaine
Hi, Le 2 mai 09 à 17:37, Tom Lane a écrit : My knowledge of AI search algorithms is about 20 years obsolete, but last I heard simulated annealing had overtaken genetic algorithms for many purposes. It might be interesting to try a rewrite based on SA; or maybe there's something better out there

[HACKERS] windows doesn't notice backend death

2009-05-02 Thread Andrew Dunstan
While trying to test Tom's theory about Windows not being able to reinitialise shared memory when a backend crashes, I was doing some testing on my Vista box. I killed a backend using the task manager, and the postmaster never noticed. pg_cancel_backend() reported correctly that the process d

Re: [HACKERS] "could not reattach to shared memory" captured in buildfarm

2009-05-02 Thread Dave Page
On Sat, May 2, 2009 at 4:21 PM, Tom Lane wrote: > I assume vaquita's configuration hasn't changed recently (Dave?) > so this seems to put the lie to the theory we've taken refuge in > that it's caused by bad antivirus software.  I don't see that it > gets us any closer to a solution though. Well

Re: [HACKERS] Updated Korean character set mappings

2009-05-02 Thread Tatsuo Ishii
> Here are update map files for our Korean character sets. The changes: > > All character sets updated to add the 3 characters added since 1998: Euro > Sign, Postal Mark, and Registered Mark. > > UHC updated to add a number of new Hanja that have been added over the years. > This brings the

Re: [HACKERS] GEQO: ERX

2009-05-02 Thread Tom Lane
Tobias Zahn writes: > I didn't not get any response to my initial message below. Now I am > wondering if nobody is into the optimizer or if my question was just too > stupid. Could you please give me some clues? Your help would really be > appreciated. Well, nobody's into GEQO very much. I took

[HACKERS] "could not reattach to shared memory" captured in buildfarm

2009-05-02 Thread Tom Lane
vaquita has an interesting report today: http://www.pgbuildfarm.org/cgi-bin/show_log.pl?nm=vaquita&dt=2009-05-01%2020:00:06 Partway through the contrib tests, for absolutely no visible reason whatsoever, connections start to fail with FATAL: could not reattach to shared memory (key=364, addr=0292

Re: [HACKERS] windows shared memory error

2009-05-02 Thread Tom Lane
Andrew Dunstan writes: > Maybe we need to look at all the places we call GetLastError(). There > are quite a few of them. It would only be an issue with syscalls that have badly designed APIs like this one. Most of the time you know that the function has failed and is supposed to have set the e

Re: [HACKERS] windows shared memory error

2009-05-02 Thread Andrew Dunstan
Tom Lane wrote: Now this would only explain problems if there were some code path through the postmaster that could leave the errno set to ERROR_ALREADY_EXISTS (a/k/a EEXIST) when this code is reached. I'm not sure there is one, and I have even less of a theory as to why system load might mak

Re: [HACKERS] GEQO: ERX

2009-05-02 Thread Tobias Zahn
Hello again, I didn't not get any response to my initial message below. Now I am wondering if nobody is into the optimizer or if my question was just too stupid. Could you please give me some clues? Your help would really be appreciated. Regards, Tobias > Hello, > I was digging through the optimi

Re: [HACKERS] Throw some low-level C scutwork at me

2009-05-02 Thread Nikhil Sontakke
Hi, > > OK, so, when I initially started catching up on this thread, I was > > kind of feeling annoyed at Tom, and I still wish he'd say something > > along the lines of "I did not mean to give offense and I'm sorry if my > > words came across in a way that I did not intend" rather than just > > e