"Greg Smith" <[EMAIL PROTECTED]> writes: > I'm mostly done with my review of the "Automatic adjustment of > bgwriter_lru_maxpages" patch. In addition to issues already brought up with > that code, there are some small things that need to be done to merge it with > the recent pg_stat_bgwriter patch, and I have some concerns about its > unbounded > scanning of the buffer pool; I'll write that up in more detail or just submit > an improved patch as I get time this week.
I had a thought on this. Instead of sleeping for a constant amount of time and then estimating the number of pages needed for that constant amount of time perhaps what bgwriter should be doing is sleeping for a variable amount of time and estimating the length of time it needs to sleep to arrive at a constant number of pages being needed. The reason I think this may be better is that "what percentage of the shared buffers the bgwriter allows to get old between wakeups" seems more likely to be a universal constant that people won't have to adjust than "fixed time interval between bgwriter cleanup operations". Just a thought. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(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
