postgresql.conf question... CPU spikes

[Bala Venkat <akpgeek@xxxxxxxxx>]

Hi all -

       We are running postgres 9.0 ( 32 bit ) + postgis 1.5.2 on Solaris Sparc M5000 with 64GB .  Recently we are getting CPU utilitzation to 99% .

In the config file

shared_buffers=2GB.

work_mem = 128MB

effective_cache_size=48GB

maintaince_work_mem= 500MB

max_connections = 300

When the CPU spikes happens, when I look at the pg_stat_activity log, the queries where current_query not like '%<IDLE>%' are between 100-110.

Do you think , I have to reduce the effective_cache and work_mem for this?

Thanks for your help.