Re: [PERFORM] Concurrency issue under very heay loads

2009-07-17 Thread Haszlakiewicz, Eric
>-Original Message- >From: pgsql-performance-ow...@postgresql.org > >We use a typical counter within a transaction to generate >order sequence number and update the next sequence number. >This is a simple next counter - nothing fancy about it. When >multiple clients are concurrently a

Re: [PERFORM] Concurrency issue under very heay loads

2009-07-17 Thread Craig Ringer
On Thu, 2009-07-16 at 00:11 -0600, Scott Marlowe wrote: > As others have said, a serial is a good idea, HOWEVER, if you can't > have gaps in sequences, or each customer needs their own sequence, > then you get to lock the rows / table / etc that you're mucking with > to make sure you don't issue t

Re: [PERFORM] Concurrency issue under very heay loads

2009-07-16 Thread Albe Laurenz
Raji Sridar wrote: > We use a typical counter within a transaction to generate > order sequence number and update the next sequence number. > This is a simple next counter - nothing fancy about it. When > multiple clients are concurrently accessing this table and > updating it, under extermely

Re: [PERFORM] Concurrency issue under very heay loads

2009-07-15 Thread Scott Marlowe
On Wed, Jul 15, 2009 at 10:59 PM, Raji Sridar (raji) wrote: > Hi, > > We use a typical counter within a transaction to generate order sequence > number and update the next sequence number. This is a simple next counter - > nothing fancy about it.  When multiple clients are concurrently accessing >

Re: [PERFORM] Concurrency issue under very heay loads

2009-07-15 Thread ramasubramanian
Hi, Are you using automatic sequence increment in table? - Original Message - From: Raji Sridar (raji) To: pgsql-gene...@postgresql.org ; pgsql-performance@postgresql.org Sent: Thursday, July 16, 2009 10:29 AM Subject: [PERFORM] Concurrency issue under very heay loads Hi,