Hoss,
: 1) Any recommendations on which best to sub-class? I'm guessing, for this > : scenario with "rare" batch puts and no evictions, I'd be looking for get > : performance. This will also be on a box with many CPUs - so I wonder if > the > : older LRUCache would be preferable? > > i suspect you are correct ... the entire point of the other caches is > dealingwith faster replacement, so you really don't care. > > You might even find it worth while to write your own > "NoReplacementCache" from scratch backed by a HashMap (instead of the > LinkedHashMap used in LRUCache) I really like this idea (roll-your-own cache using a simple HashMap). However, as much searching as I've done, I've come up short on anything that describes concurrency in Solr. The short question is, for such a cache, do I need to worry about concurrent access (I'm guessing that the firstSearcher QuerySenderListener process would be single-threaded/non-concurrent, and thus writes would never be an issue - is this correct?) - e.g. for my case, would I back the "NoReplacementCache" with a HashMap or ? The bigger question is: what are the parallel task execution paths in Solr and under what conditions are they possible? Thanks again, Aaron