From: tsunakawa.ta...@fujitsu.com <tsunakawa.ta...@fujitsu.com> > Can you measure the time DropRelFileNodeBuffers()? You can call > GetTimestamp() at the beginning and end of the function, and use > TimestampDifference() to calculate the difference. Then, for instance, > elog(WARNING, "time is | %u.%u", sec, usec) at the end of the function. You > can use any elog() print format for your convenience to write shell commands > to > filter the lines and sum up the total.
Before doing this, you can also do "VACUUM (truncate off)" to see which of the garbage collection or relation truncation takes long time. The relation truncation processing includes not only DropRelFileNodeBuffers() but also file truncation and something else, but it's an easy filter. Regards Takayuki Tsunakawa
