On Fri, Apr 8, 2011 at 4:00 AM, Gipsz Jakab <clausewitz45@xxxxxxxxx> wrote:
My question is the following: if this is a dedicated database server, with maximum 30 users (but they are using ODBC with Microsoft Acces, and each of them generating 4-6 connection at the same time), and other 200 people will use this server through drupal, php, apache not in daily basis, but weekly, what is the ideal memory configuration?
if it is a dedicated DB server, then give shared memory about 1/4 of the RAM, and perhaps a slightly larger maintenance work mem. depending on your workload you may want to increase the checkpoint segments (if write-mostly, then add more segments).
Here is what I use on my FreeBSD 8, Pg 9 big-memory servers. these have 24GB or more of RAM and are attached to SSD external storage for the database:
max_connections = 200
shared_buffers = 5120MB
work_mem = 512MB
maintenance_work_mem = 1024MB
max_stack_depth = 8MB
vacuum_cost_delay = 15checkpoint_segments = 64
checkpoint_timeout = 15min
checkpoint_completion_target = 0.8
random_page_cost = 1.0 # RAM disk. set equal seq_page_cost
effective_cache_size = 6400MB # shared_buffers + `sysctl -n vfs.hibufspace` / 8192 (BLKSZ)
for individual complicated queries, you can increase the sort mem and work mem on a per-connection basis as needed.
After the settings in the postgresql.conf our system is much faster, and no more error messages in the postgres.log, but If I try to drop a table, or add a new one, our system is stopping, until I kill the process, which is dropping or adding a table.
Is something else using the table you want to drop and blocking the drop statement from taking the locks it needs? It should be fairly instant.
