On Mon, Oct 26, 2015 at 8:30 PM, 657985...@qq.com <657985...@qq.com> wrote:
> Dear sir: > Recently a wired question about postgresql database really > bothered me a lot, so i really need your help. Here is the problem, in the > most situations the postgre database work very well, Average 3500tps/s > per day, the cpu usage of its process is 3%~10% and every query can be > responsed in less than 20ms, but sometimes the cpu usages of its process > can suddenly grow up to 90%+ , at that time a simple query can cost > 2000+ms. ps: My postgresql version is 9.3.5 and the database is oltp > server. > >From all the lseeks on the same file, it looks like you are doing a sequential scan on a table for the inside of a nested loop. What is the query it is running, and what is the execution plan for it? To get that, run: explain (analyze, buffers) select o_count from .... Cheers, Jeff
