On Mon, 2014-05-12 at 14:10 -0700, Jaikit Savla wrote: > I have seen similar issues sometimes - while running with 512 concurrent > connections using HttpClient 4.3 (Noticed all threads stuck in > java.lang.reflect.Proxy.getProxyClass0 in jstack log). I found some > discussion online regarding improving the performance in latest jre but have > not tried running my application with jdk8 yet. > > http://mail.openjdk.java.net/pipermail/core-libs-dev/2013-April/subject.html#15854 > > Jaikit >
Jaikit & Daniel, Dynamic proxies help eliminate a great deal of unnecessary code but I have no problem with replacing them with hand crafted classes in order to reduce lock contention. Feel free to raise an enhancement request and contribute patches. Oleg > On Monday, May 12, 2014 11:17 AM, Oleg Kalnichevski <ol...@apache.org> wrote: > > On Mon, 2014-05-12 at 13:21 +0100, Daniel Feist wrote: > > >> 2) Can I expect 4.2 to scale better? > > > > > > I do not think so. In my tests HC 4.3 performs better than 4.2. There > > > have also been reports > > > > Even with high concurrency of say 200 and high TPS, for example in a > > http proxy scenario? > > > > Yes, also with over 200 concurrent connections. However, for HTTP proxy > scenarios one may be advised to consider using a non-blocking model. > > > >> 3) Is there a way of configuring 4.3.3 to not use proxys? > > > > > > No, there is not. The cost of dynamic proxies in modern JREs is believed > > > to be low. > > > > The problem I see isn't the use of proxies, it is in the creation of > > these proxy instances which is synchnorized on a HashMap 'cache' in > > two places in java.lang.reflect.Proxy.getProxyClass0(ClassLoader, > > Class<?>...). This is visible in the profiler screenshot I shared > > too. > > > > This probably isn't an issue with low concurrency, or high concurrency > > and low TPS, but in my testing/profiling it comes up as an issue. > > > > I use this micro-benchmark to benchmark HttpClient performance between > versions as well compared to other implementations. > > http://wiki.apache.org/HttpComponents/HttpClient3vsHttpClient4vsHttpCore > > I am open to the idea of replacing dynamic proxies with hand crafted > classes, but I would like to see more evidence that > java.lang.reflect.Proxy is indeed a bottleneck. > > Oleg > > > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: httpclient-users-unsubscr...@hc.apache.org > For additional commands, e-mail: httpclient-users-h...@hc.apache.org > > --------------------------------------------------------------------- > To unsubscribe, e-mail: httpclient-users-unsubscr...@hc.apache.org > For additional commands, e-mail: httpclient-users-h...@hc.apache.org > --------------------------------------------------------------------- To unsubscribe, e-mail: httpclient-users-unsubscr...@hc.apache.org For additional commands, e-mail: httpclient-users-h...@hc.apache.org
