Re: Clock sweep not caching enough B-Tree leaf pages?

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
Iam 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
cannottraverse the entire list and then find all the buffers with refcount 0 and then do another traversal to find the
oldestone.
 

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                       jim@nasby.net
512.569.9461 (cell)                         http://jim.nasby.net