[GENERAL] Reduce the time to know trigger_file's existence
Hi, We are trying to introduce a thread that monitors the creation of the trigger_file. As and when the file is created, the process that monitors postgres server needs to be notified through the inotify API. This is to reduce the 3-4 seconds delay that exists with the current implementation in postgres. As per the current implementation, the thread checks for the existence of the file every 5 seconds. If the file got created just 1 second after the sleep, there is a wait time of 4 seconds before we know whether the file is present or not. We intend to avoid this delay by using inotify(). PostgreSQL version number you are running: postgres 9.1.5 How you installed PostgreSQL: Downloaded and compiled the sources Does anyone have suggestions on the appropriate place to add inotify_add_watch to achieve our objective? Thanks in advance.
[GENERAL] Re: [GENERAL] Reduce the time to know trigger_file's existence
Hi, Can Latch - that postgres already uses, be used to achieve the same? On Tue, Sep 4, 2012 at 6:31 AM, Craig Ringer ring...@ringerc.id.au wrote: On 09/03/2012 04:30 PM, Harshitha S wrote: Hi, We are trying to introduce a thread that monitors the creation of the trigger_file. As and when the file is created, the process that monitors postgres server needs to be notified through the inotify API. File system notification APIs aren't portable. If you want to implement this you'll need to support at least the Windows FSNotify stuff, notification features compatible with several different Linux versions and with the BSDs, with a fallback to polling for other platforms. For Windows: http://msdn.microsoft.com/en-**us/library/windows/desktop/** aa365261(v=vs.85).aspxhttp://msdn.microsoft.com/en-us/library/windows/desktop/aa365261%28v=vs.85%29.aspx For Linux it appears that inotify has been present since 2005: http://en.wikipedia.org/wiki/**Inotifyhttp://en.wikipedia.org/wiki/Inotify but it's probably best to add a configure test and fall back to polling if it isn't found. This will mean adding a new internal API and then adding backend/port/ implementations for various platforms, as well as taking the current code and splitting it out into a port file that gets used if no other is chosen. This page is likely to be useful: http://wiki.postgresql.org/**wiki/So,_you_want_to_be_a_**developer%3Fhttp://wiki.postgresql.org/wiki/So,_you_want_to_be_a_developer%3F -- Craig Ringer
Re: [GENERAL] could not create file base/16384/11500: File exists
Hi, The postgres server version is 9.0.4 on the Linux platform. The vaccum - related settings have default values. If it is OID wrap around, how to resolve it? Regards, Harshitha 2011/10/10 Filip Rembiałkowski plk.zu...@gmail.com Hello, You gave much too little information. Please see http://wiki.postgresql.org/wiki/Guide_to_reporting_problems Especially: - server version, platform - vacuum-related settings It *might* be OID wraparaound. 2011/10/10 Harshitha S hershe...@gmail.com Hi, We are the following msg in the postgres logs. could not create file base/16384/11500: File exists Some links indicate that the issue is related to OIDs. Please help me in understanding why the message is appearing and how the issue can be resolved. Regards, Harshitha
Re: [GENERAL] could not create file base/16384/11500: File exists
Also, this is the case of first startup of the postgres server. This msg is shown in the startup logs. 2011/10/10 Harshitha S hershe...@gmail.com Hi, The postgres server version is 9.0.4 on the Linux platform. The vaccum - related settings have default values. If it is OID wrap around, how to resolve it? Regards, Harshitha 2011/10/10 Filip Rembiałkowski plk.zu...@gmail.com Hello, You gave much too little information. Please see http://wiki.postgresql.org/wiki/Guide_to_reporting_problems Especially: - server version, platform - vacuum-related settings It *might* be OID wraparaound. 2011/10/10 Harshitha S hershe...@gmail.com Hi, We are the following msg in the postgres logs. could not create file base/16384/11500: File exists Some links indicate that the issue is related to OIDs. Please help me in understanding why the message is appearing and how the issue can be resolved. Regards, Harshitha
[GENERAL] could not create file base/16384/11500: File exists
Hi, We are the following msg in the postgres logs. could not create file base/16384/11500: File exists Some links indicate that the issue is related to OIDs. Please help me in understanding why the message is appearing and how the issue can be resolved. Regards, Harshitha
[GENERAL] Tracing in Postgres
Hi, I am trying to integrate a tracing framework in the Postgres code. I need to know if elog.c under backend/utils/error is the place where the changes can be made. The tracing framework that I want to integrate has some additional capability. I want to replace the tracing and logging functionality in the existing Postgres framework with the APIs used in this framework without making changes in every file. If anybody has any inputs on this, please help me. Thanks, Harshitha
