Alvaro Herrera <[EMAIL PROTECTED]> wrote: > What I'm requesting here is that the sleep in count_nondeletable_pages() > be removed and that change backpatched to 8.2 and 8.1.
Agreed. We'd better to shorten the exclusive locking as far as possible. > We don't know how many pages we can truncate until after we have > acquired the exclusive lock and examined the pages in question, scanning > backwards from the end of the table. But many OSes do not care about read-ahead in backward scanning. I have a test result that shows truncating a large part of table takes very long time. Is it better better to change it to forward scanning? For example, starting with (tail of the file - 16MB) and scanning 16MB of segment forward to decide the position for truncation. If we can truncate all of the segment, do recheck from (tail of the file - 32MB) and repeat. Regards, --- ITAGAKI Takahiro NTT Open Source Software Center ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
