At 09:57 PM 7/17/2002 +0000, you wrote: I am bumping my thread in the hopes that some people may not have seen it before, or that others may have come across some new ideas.
Also, for informational purposes, the time that I am actually measuring is the actual time that the transform call takes. In both cases, the Source is a StreamSource that has a ByteArrayInputStream at its base, and the Result is a StreamResult that is going to a ByteArrayOutputStream. Can anyone think of anything, either java related, Tomcat related, xalan related, etc. that would cause the time for the same transform to be much much slower from within a servlet running in Tomcat as opposed to a test program run from command line. Thanks in advance, Mario- >Hello all, > >I have a small thread going on the xalan-j-users list, but I thought I >would ask a similar question here since the performance issue involved has >tomcat as one of its major components. > > >My original email: > >"I am running Tomcat 3.3.1 with the JRE 1.3.1_03 server vm, and Xalan-J 2.4D1. > >I wrote a small test program that performs a couple of transforms on some >data that I have that happens to be a decent size. This transforms it in >about 40 seconds each for the first pass, and usually 16 and 26 seconds >each for the subsequent iterations. > >When I run the same two transforms from within a servlet running under >Tomcat, it takes an unbelievably long time. We are talking on the order of >6-8 min. for the first transform, and 2-3 min for the second one. > >For further clarification, the transformers are always derived from a >Templates object. The system is a P3-800 with 256 MB of memory. When I run >my test program, it sucks nerely 100% CPU for the whole time, and chews a >healthy amount of memory. When I run from tomcat, it spikes the CPU to >varying levels but never chews it consistently, while at the same time >consuming apparently a bit less memory (or quickly gc'ing the memory). > >In both cases, the Java heap is set to minimum 128 and maximum 512. > >I would expect the time under the servlet to be a bit slower, primarily >because there are other things that I am doing there that I am not doing >in my test program, but these numbers are downright painful." > >Some further information from discussions: > >Stylesheet optimization is something to look at, but regarding the current >case the stylesheets are the same for bothe the test program and the >servlet case. > >I am more convinced that this has to do with the CPU usage. When I run my >test program, it uses almost all of the CPU for the entire run, and >consequently things get done quickly. > >When run from within the servlet, the CPU varies from around 3% to about >30-45%, and only rarely spikes above that. > >Does anyone know what would cause this, or a way to tell it to go ahead >and chew the CPU so as to get done with processing as fast as possible? > >As for the heap size issue, I tried setting it to -Xms128m and -Xmx128m >and ended up blowing the heap under both my test program and tomcat. I >don't really think it is a heap issue because this performance is similar >on other machines we have tested on that have 1GB of memory. > >Any thoughts, ideas, or experiences to share? > >Thanks in advance, > >Mario- -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
