On 1/29/13 5:02 PM, Manik Surtani wrote: > Thinking about Sanne's idea re: a clock service and not continuously relying > on System.cTM, I stumbled upon this: > > https://blogs.oracle.com/ksrini/entry/we_take_java_performance_very > > The last section re: caching is interesting. > > Having all code use a Clock.currentTimeMillis() and having an implementation > that kicks off a scheduled task to update a cached value every $frequency > millis (by using the System call) is probably the correct way to implement > something like this, but this adds complexities/concerns: > > * CPU cache line blowing away (see article) > * Context switching > * Managing an extra service thread > * Probably an additional configuration option to configure that thread, its > priority and frequency. If frequency is dropped (e.g., every second) I > suppose the perf gains would be huge. > > JGroups - does JGroups make many and frequent calls to System.cTM as well?
No; currentTimeMillis() is used in tasks that run every few seconds, otherwise we use nanoTime(). -- Bela Ban, JGroups lead (http://www.jgroups.org) _______________________________________________ infinispan-dev mailing list [email protected] https://lists.jboss.org/mailman/listinfo/infinispan-dev
