Really sorry for the lack of information, but I did asked if the slow queries could affect those simple one:
'so I wonder could this simple select is innocent and affected badly by other queries? '
I didn't mention the connections number because I don't think my app is that busy, and the large number connections was caused by slow queries.
I was wrong, everything is connected, too many factor could end with the result,I am really sorry, I will tell everything I knew the next time:)
I learnt a lot during the back and forth!
On Thursday, July 12, 2012, Craig Ringer wrote:
On 07/11/2012 07:40 PM, Yan Chunlu wrote:
could that because of my system is really busy? 1, postgresql always have 400+ connections(dozens of python process using client pool)
2, the query peak is 50+/s
3, I do have some bad performance sql executing periodically, need 100+ second to complete. could those bad performance sql influence others? because when I execute those simple sql directly, they was fast. but the slow query log shows it took too much time.
Oh, come on, these are the sorts of things you tell us
when you ask your question, not days later after lots of back-and-forth discussion.
--
Craig Ringer