Re: [HACKERS] Some questions about mammoth replication

2007-10-12 Thread Alexey Klyukin
Hannu Krosing wrote: We have hooks in executor calling our own collecting functions, so we don't need the trigger machinery to launch replication. But where do you store the collected info - in your own replication_log table, or do reuse data in WAL you extract it on master befor

Re: [HACKERS] Some questions about mammoth replication

2007-10-12 Thread Alexey Klyukin
Hannu Krosing wrote: We don't use either a log table in database or WAL. The data to replicate is stored in disk files, one per transaction. Clever :) How well does it scale ? That is, at what transaction rate can your replication keep up with database ? This depend on a number of

Re: [HACKERS] Some questions about mammoth replication

2007-10-12 Thread Hannu Krosing
Ühel kenal päeval, R, 2007-10-12 kell 12:39, kirjutas Alexey Klyukin: Hannu Krosing wrote: We have hooks in executor calling our own collecting functions, so we don't need the trigger machinery to launch replication. But where do you store the collected info - in your own

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Alexey Klyukin
Hello, Hannu Krosing wrote: Here come my questions : From looking at http://www.commandprompt.com/images/MR_components.jpg it seems that you don't do replication just from WAL logs, but also collect some extra info inside postgreSQL server. Is this so ? If it is, then in what way does

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Andreas Pflug
Alexey Klyukin wrote: For what use cases do you think your WAL-based approach is better than Slony/Skytools trigger-based one ? A pure trigger based approach can only replicate data for the commands which fire triggers. AFAIK Slony is unable to replicate TRUNCATE command It could

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Marko Kreen
On 10/11/07, Alexey Klyukin [EMAIL PROTECTED] wrote: Hannu Krosing wrote: For what use cases do you think your WAL-based approach is better than Slony/Skytools trigger-based one ? A pure trigger based approach can only replicate data for the commands which fire triggers. AFAIK Slony is

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Alexey Klyukin
Marko Kreen wrote: On 10/11/07, Alexey Klyukin [EMAIL PROTECTED] wrote: Hannu Krosing wrote: For what use cases do you think your WAL-based approach is better than Slony/Skytools trigger-based one ? A pure trigger based approach can only replicate data for the commands which fire

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Joshua D. Drake
On Thu, 11 Oct 2007 19:10:18 +0300 Alexey Klyukin [EMAIL PROTECTED] wrote: Marko Kreen wrote: On 10/11/07, Alexey Klyukin [EMAIL PROTECTED] wrote: Hannu Krosing wrote: For what use cases do you think your WAL-based approach is better than Slony/Skytools trigger-based one ? A

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Hannu Krosing
Ühel kenal päeval, N, 2007-10-11 kell 18:25, kirjutas Alexey Klyukin: Hello, Hannu Krosing wrote: Here come my questions : From looking at http://www.commandprompt.com/images/MR_components.jpg it seems that you don't do replication just from WAL logs, but also collect some extra

Re: [HACKERS] Some questions about mammoth replication

2007-10-11 Thread Joshua D. Drake
On Thu, 11 Oct 2007 21:58:45 +0300 Hannu Krosing [EMAIL PROTECTED] wrote: We have hooks in executor calling our own collecting functions, so we don't need the trigger machinery to launch replication. But where do you store the collected info - in your own replication_log table, No, we