I am using Postgresql 8.1 in 8-cpu cores with 32 gb ram with CestOS 5. I have different DBs in the system and the large one is 12 GB and it is a CRM DB and heavily used. Every day after 1 pm the system gets slow and after analyzing the nmon spreadsheet, I found that IO spike at that period. Users write data much at that period of time. DB parameters are as follows: max_connections= 500 shared_buffers=122144 effective_cache_size = 1835010 work_mem = 8192 max_fsm_pages= 356656 fsync=on commit_delay=0 commit_siblings= 5 random_page_cost = 0.01 default_statistics_target=100 wah_buffers = 500
Any idea please how to find the bottleneck and improve performance. Let me know if any more information is needed.
