On 5/11/11 5:42 AM, Mark Thomas wrote: > On 11/05/2011 11:31, Mark Thomas wrote: >> On 11/05/2011 04:34, Phil Steitz wrote: >>> On 5/10/11 7:26 PM, Phil Steitz wrote: >>>> On 5/10/11 8:48 AM, ma...@apache.org wrote: >>>>> Author: markt >>>>> Date: Tue May 10 15:48:22 2011 >>>>> New Revision: 1101516 >>>>> >>>>> URL: http://svn.apache.org/viewvc?rev=1101516&view=rev >>>>> Log: >>>>> Move to using LinkedBlockingDeque for the queue of idle objects. >>>> Definitely simpler, cleaner code, but seems there will be no easy >>>> way to enable fairness and some badly "unfair" stuff can happen when >>>> clients get instances under maintenance. In theory, an unlucky >>>> client could wait forever. Do we have any data on how "unfair" >>>> LinkedBlockingDeque can be? ArrayBlockingQueue is an alternative >>>> that does support fairness; but then I guess we lose LIFO/FIFO >>>> control and probably performance. Any ideas how we could get >>>> fairness, or at least some control over fairness to work? Another >>>> thing to think about is whether clients are better off waiting for >>>> the state change on instances under maintenance than getting back in >>>> line for the next available instance. (I now see the fairness TODO >>>> in TestGOP :) >>> After looking quickly at the Harmony code for LinkedBlockingDeque, >>> we may be able to solve both the 1.6 problem and fairness by >>> bringing that source in and just making the ReentrantLock that it >>> uses configurable to be either fair or not (as ArrayBlockingQueue >>> does). Might be naive, but might work. >> I like it. A lot. Great idea. > Better still, it is faster than whatever Oracle wrote for Java 6 :) > With this in place, DBCP is slightly faster than jdbc-pool for > jdbc-pools checkout thread tests. This is only two microbenchmarks > (there are lots of other tests where jdbc-pool is faster but I haven't > optimized DBCP for those yet) but it is a promising sign. > > I just need to tidy up the code before I check it in.
Great! I also now have [performance] set up to run pool2 tests directly. I have just started testing. I will post results as I get them and also for [dbcp] with the new pool. Don't forget to re-enable the fairness unit test once that is working. Phil > Mark > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
