Hi Lee, I wouldn't expect multiple reader threads to conflict in the absence of mutation or locking. My first impulse when reading your message was to have a look at what the garbage collector is doing as, in my experience, the "initially fast but gradual slowdown" sort of behaviour ends up being the garbage collector getting busier and busier over time.
Perhaps a good first step would be to start your JVM with the "-verbose:gc" switch and re-run your tests. That should print out some diagnostic information about how often the garbage collections are happening. Cheers, Mark Lee Spector <lspec...@hampshire.edu> writes: > I've been running the genetic programming system that I mentioned in an > earlier post (http://hampshire.edu/lspector/clojush/) on a dual > quad-core mac and seeing some very nice concurrency, with up to 1300% > CPU utilization in some configurations. (Apparently there's some magic > that lets the 8 cores in this machine act like 16 to some extent -- I > don't know the details but it's nice.) > > However, sometimes I get more and sometimes I get less, and I also get > decreasing amounts of it over time, which I find puzzling. For example, > running the system on a hard problem over night last night I was > initially getting peaks of about 1100% CPU (between the synchronization > bottlenecks), but this morning it was still running but the peaks were > only about 300%. > > The things that are happening concurrently in this program never have to > write to the same places, but sometimes they do have to read from the > same places and I'm wondering if this is responsible for some of what > I'm seeing. -- Mark Triggs <mark.h.tri...@gmail.com> -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
