OK, so if it knew that all vacuumable tuples could be found in 492 pages, and
it scanned only those pages, then how could it be that it reports 16558
removable tuples from those 492 pages, when it has already reported earlier
that it removed 45878 tuples -- a number we know in fact to be correct?
On 10-08-06 11:45 AM, Gordon Shannon wrote:
OK, so if it knew that all vacuumable tuples could be found in 492 pages, and
it scanned only those pages, then how could it be that it reports 16558
removable tuples from those 492 pages, when it has already reported earlier
that it removed 45878
Excerpts from Brad Nicholson's message of vie ago 06 12:01:27 -0400 2010:
On 10-08-06 11:45 AM, Gordon Shannon wrote:
OK, so if it knew that all vacuumable tuples could be found in 492 pages,
and
it scanned only those pages, then how could it be that it reports 16558
removable tuples
Yes, and also from the original post:
3 INFO: scanned index authors_archive_pkey to remove 45878 row
versions
4 DETAIL: CPU 0.05s/0.34u sec elapsed 0.41 sec.
5 INFO: authors_archive: removed 45878 row versions in 396 pages
6 DETAIL: CPU 0.00s/0.00u sec elapsed 0.00 sec.
Line 5 is
Alvaro Herrera alvhe...@commandprompt.com writes:
Excerpts from Brad Nicholson's message of vie ago 06 12:01:27 -0400 2010:
It found 45878 dead tuples in 396 pages for the index authors_archive_pkey.
It found 16558 dead tuples in 492 pages for the table authors_archive.
But why did it choose
That last message prints tups_vacuumed, but those other ones are counting
all the removed item pointers. So apparently Gordon had a whole lot of
pre-existing DEAD item pointers. I wonder why ...
Perhaps this will help. Here's the entire test.
Start with a newly loaded table with 5,063,463
Hi, Running 8.4.4 on Centos. A couple of these numbers don't make sense to
me.
(I added line numbers for reference)
1 vacuum verbose authors_archive;
2 INFO: vacuuming public.authors_archive
3 INFO: scanned index authors_archive_pkey to remove 45878 row versions
4 DETAIL: CPU
Gordon Shannon gordo...@gmail.com writes:
Hi, Running 8.4.4 on Centos. A couple of these numbers don't make sense to
me.
(I added line numbers for reference)
11 INFO: authors_archive: found 16558 removable, 7300 nonremovable row
versions in 492 out of 51958 pages
The key point here is
