----- Original Message ----- From: "Glenn Nielsen" <[EMAIL PROTECTED]> To: "Tomcat Developers List" <[EMAIL PROTECTED]> Sent: Friday, January 17, 2003 7:04 PM Subject: Re: DO NOT REPLY [Bug 16001] - Tag.release() not invoked
> Costin Manolache wrote: > > Hans Bergsten wrote: > > > > > >>evaluation all in one place. To make things even easier, these tag > >>handlers can _not_ be reused at all. Benchmarks with modern JVMs show > >>that the gain from reuse is not worth all the trouble. So, for new > >>tags we recommend using the SimpleTag API which takes care of the > >>problem by forbidding reuse. > > > > > > Wow. I would be _very_ curious to see those benchmarks and the "modern" > > JVM that was used. > > > > All my tests ( including JDK1.4, IBM vms, GCJ ) show that reusing is well > > worth the trouble - at least if you have 100s of requests per second > > ( it is not worht the trouble for very low loads ). But I'm happy to > > hear that I'm wrong. > > > > Costin > > Hear, Hear!! > > I saw a significant, measureable improvement in performance when I upgraded > our production systems to Jasper 2 with tag pooling from Jasper 1 without. > CPU load on the production server dropped around 30%, request latency was > reduced significantly, etc. The app server handles 30k-100K requests per day. > This is on a Sun dual CPU E250, 768MB of Ram, that is run solely as an app server. > OS is Solaris 8, JVM is 1.3.1 using HotSpot server, and I have spent time tuning > the JVM stack and GC java startup args. > > Tag pooling elminates significant amounts of GC. That is where the real > benefit of tag pooling comes from. With tag pooing the frequency and > length of GC's are reduced a great deal. > I saw just the opposite. Jasper2 with tag-pooling was a real dog (the time spent in synchronized methods to maintain the pool completely swamped any benefit from GC). After patching my copy to make don't-tag-pool the default (since there isn't any way to do this in the config :( ), then Tomcat 4.1/Jasper2 was about 60% faster that Tomcat 3.3/Jasper1 when I 'ab' benchmarked it against one of my more complex pages. > Glenn > > > -- > To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> > For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> > -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
