On 4/18/14, 2:51 PM, Atri Sharma wrote:
I feel that if there is no memory pressure, frankly it doesnt matter much about what gets out and what not. The case I am specifically targeting is when the clocksweep gets to move about a lot i.e. high memory pressure workloads. Of course, I may be totally wrong here.
Well, there's either memory pressure or there isn't. If there isn't then it's all moot *because we're not evicting anything*.
One thing that I discussed with Merlin offline and am now concerned about is how will the actual eviction work. We cannot traverse the entire list and then find all the buffers with refcount 0 and then do another traversal to find the oldest one.
This is why OSes use multiple page pools. If we're going to use a clock sweep at all I think we need to use the same. Every time we discuss this stuff it feels like we're completely reinventing the wheel that was solved by OSes years ago. :( -- Jim C. Nasby, Data Architect j...@nasby.net 512.569.9461 (cell) http://jim.nasby.net -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
