Hi again all, I've tested postgres 7.3.4 on Linux version 2.4.17 and this is what I found :
The initial instance took up 8372K and this fluctuated between +- 8372K and 10372K, plus +- 3500K for every connection. I did quite a few transactions on both connections, plus a few vacuums and a pg_dump and the total memory usage didn't seem to go over 16M I set all the _buffers, _mem, _fsm settings to the minimum, restarted every time, but this had absolutely no noticeable increase or decrease in total memory usage. (I used a program called gmemusage to get these stats.) On the same machine , I tested postgres 7.1.2 with basically the same conf options (not _fsm) and got the following : The initial instance was 1772K and fluctuated to +- 4000K, plus +- 3400K for every connection. Doing the same transactions, vacuum + pg_dump, total memory usage didn't really go over 11M, which was exactly what I needed. Although I've lived through some of the shortcomings of 7.1.2, it is still very stable, and works perfectly for what it is going to be used for. Again, here, I was only able to restrict things a little by changing the configuration options, but no major difference in memory usage. Regards Stef On Mon, 6 Oct 2003 09:55:51 +0200 Stef <[EMAIL PROTECTED]> wrote: => Thanks for the replies, => => On Fri, 3 Oct 2003 11:08:48 -0700 => Josh Berkus <[EMAIL PROTECTED]> wrote: => => 1. Make sure that the WAL files (pg_xlog) are on a seperate disk from the => => database files, either through mounting or symlinking. => => I'm not sure I understand how this helps? => => => 2. Tweak the .conf file for low vacuum_mem (1024?), but vacuum very => => frequently, like every 1-5 minutes. Spend some time tuning your => => fsm_max_pages to the ideal level so that you're not allocating any extra => => memory to the FSM. => => => => 3. If your concern is *average* CPU/RAM consumption, and not peak load => => activity, increase wal_files and checkpoint_segments to do more efficient => => batch processing of pending updates as the cost of some disk space. If peak => => load activity is a problem, don't do this. => => => => 4. Tune all of your queries carefully to avoid anything requiring a => => RAM-intensive merge join or CPU-eating calculated expression hash join, or => => similar computation-or-RAM-intensive operations. => => Thanks, I'll try some of these, and post the results. => The actual machines seem to be Pentium I machines, => with 32M RAM. I've gathered that it is theoretically => possible, so no to go try it. => => Regards => Stef =>
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