On 20 Oct 2011, at 08:47, Galder Zamarreņo wrote:


Why are we preferring to provide more cache misses && slower
performance, to fake a slightly better precision in eviction?


I guess this is the main question, how much worse would the eviction
precision be if we only relied on the periodic eviction thread?

We did use to have a periodic eviction thread in the JBoss Cache days, but that used to cause us problems since we queued events to the cache in order to apply eviction algorithms.

That was a different case.  In JBC we picked nodes for eviction and put them on an eviction queue and they were analysed periodically.  That queue became a bottleneck.  

The suggestion here is to essentially cache time lookups so that you don't call System.cTM() all the time.  See Elias Ross' parallel post to this list about Netty's HashedWheelTimer.  

Sanne, I recall your creating a JIRA for this?

--
Manik Surtani
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Lead, Infinispan
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