Re: [PERFORM] Best tweak for fast results.. ?

2003-08-28 Thread scott.marlowe
On Tue, 26 Aug 2003, JM wrote:

 need input on parameter values on confs...
 
 our database is getting 1000 transactions/sec on peak periods..
 
 sitting on RH 7.3 
 2.4.7-10smp
 RAM: 1028400
 SWAP: 2040244

1:  Upgrade your kernel.  2.4.7 on RH3 was updated to 2.4.18-24 in March, 
and the 2.4.18 kernel is MUCH faster and has many bugs squashed.

2:  Upgrade to the latest stable version of postgresql, 7.3.4

3:  Make sure your kernels file-nr settings, and shm settings are big 
enough to handle load.  

4:  Edit the $PGDATA/postgresql.conf file to reflect all that extra cache 
you've got etc  

shared_buffers = 5000
sort_mem = 16384
effective_cache_size = (size of cache/buffer mem divided by 8192)

5:  Look at moving WAL to it's own spindle(s), as it is often the choke 
point when doing lots of transactions.

6:  Look at using more drives in a RAID 1+0 array for the data (as well as 
a seperate one for WAL if you can afford it.)

7:  Make sure your drives are mounted noatime.

8:  If you don't mind living dangerously, or the data can be reproduced 
from source files (i.e. catastrophic failure of your data set won't set 
you back) look at both mounting the drives async (the default for linux, 
slightly dangerous) and turning fsync off (quite dangerous, in case of 
crashed hardware / OS, you very well might lose data.


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[PERFORM] Best tweak for fast results.. ?

2003-08-26 Thread JM
need input on parameter values on confs...

our database is getting 1000 transactions/sec on peak periods..

sitting on RH 7.3 
2.4.7-10smp
RAM: 1028400
SWAP: 2040244

queries are just simple select statements based on timestamps, varchars...
less on joins... on a 300K rows..


TIA

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