Greg Stark <[EMAIL PROTECTED]> writes: > Tom Lane <[EMAIL PROTECTED]> writes: >> That surprises me too --- can you provide details on the test case so >> other people can reproduce it? AFAIR the only performance difference >> between SERIALIZABLE and READ COMMITTED is the frequency with which >> transaction status snapshots are taken; your report suggests you were >> spending 30% of the time in GetSnapshotData, which is a lot higher than >> I've ever seen in a profile.
> Perhaps it reduced the amount of i/o concurrent vacuums were doing? Can't see how it would do that. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match