It just seems that the more activity there is (that is when there's a lot of disk activity) the checkpoints happen quicker too.
Here's a snapshot from the /var/log/messages - Oct 26 17:21:22 vl-pe6650-003 postgres[13978]: [2-1] LOG: recycled transaction log file "0000000B0000007E" Oct 26 17:21:22 vl-pe6650-003 postgres[13978]: [3-1] LOG: recycled transaction log file "0000000B0000007F" ... Oct 26 17:26:25 vl-pe6650-003 postgres[14273]: [2-1] LOG: recycled transaction log file "0000000B00000080" Oct 26 17:26:25 vl-pe6650-003 postgres[14273]: [3-1] LOG: recycled transaction log file "0000000B00000081" Oct 26 17:26:25 vl-pe6650-003 postgres[14273]: [4-1] LOG: recycled transaction log file "0000000B00000082" ... Oct 26 17:31:27 vl-pe6650-003 postgres[14508]: [2-1] LOG: recycled transaction log file "0000000B00000083" Oct 26 17:31:27 vl-pe6650-003 postgres[14508]: [3-1] LOG: recycled transaction log file "0000000B00000084" Oct 26 17:31:27 vl-pe6650-003 postgres[14508]: [4-1] LOG: recycled transaction log file "0000000B00000085" ... I have increased them from default 3 to 15. Haven't altered the frequency though.... Thanks, Anjan -----Original Message----- From: Tom Lane [mailto:[EMAIL PROTECTED] Sent: Tuesday, October 26, 2004 5:53 PM To: Anjan Dave Cc: Rod Taylor; Postgresql Performance Subject: Re: [PERFORM] can't handle large number of INSERT/UPDATEs "Anjan Dave" <[EMAIL PROTECTED]> writes: > None of the locks are in state false actually. In that case you don't have a locking problem. > I don't have iostat on that machine, but vmstat shows a lot of writes to > the drives, and the runnable processes are more than 1: I get the impression that you are just saturating the write bandwidth of your disk :-( It's fairly likely that this happens during checkpoints. Look to see if the postmaster has a child that shows itself as a checkpointer in "ps" when the saturation is occurring. You might be able to improve matters by altering the checkpoint frequency parameters (though beware that either too small or too large will likely make matters even worse). regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
