> Using sync_file_range you can specify the set of blocks to sync and
> then block on them only after some time has passed. But there's no
> documentation on how this relates to the I/O scheduler so it's not
> clear it would have any effect on the problem. We might still have to
> delay the begining of the sync to allow the dirty blocks to be synced
> naturally and then when we issue it still end up catching a lot of
> other i/o as well.
This *really* sounds like we should be working with the FS geeks on
making the OS do this work for us. Greg, you wanna go to LinuxCon next
year?
-- -- Josh Berkus PostgreSQL Experts Inc.
http://www.pgexperts.com