Robert, the bulk of these synchronization/performance fixes (mostly from Toadie) will be in 2.7.1 to be release. The 2.7.1 release will be out Friday November 24, 2006 if all goes well. A number of similar patches from Dave Brosius were also applied, although the performance implications of his patches were not so clear, they were there mostly to move up to the "new" collection classes in JRE 1.2
Of course a whole lot of other fixes will be included since this is the first release since Aug 8, 2005 for 2.7.0. The laundry list will be in the release notes. - Brian - - - - - - - - - - - - - - - - - - - - Brian Minchau Xalan PMC mailto:[EMAIL PROTECTED] "Robert Houben" <[EMAIL PROTECTED] sionware.net> To <xalan-dev@xml.apache.org>, 11/17/2006 04:38 <xalan-j-users@xml.apache.org> PM cc Subject RE: Performance problem for Xalan-J on intel-dual core Thanks for the heads-up and thanks especially to Toadie! This is very useful information to have, as we have quite a few users running multiprocessor and dual core systems using Xalan. Do you know what version of Xalan these changes will get into? -----Original Message----- From: Brian Minchau [mailto:[EMAIL PROTECTED] Sent: Friday, November 17, 2006 1:27 PM To: xalan-dev@xml.apache.org; xalan-j-users@xml.apache.org Subject: Performance problem for Xalan-J on intel-dual core Over the last week I've been working with Toadie (a Xalan user) who had some very serious performance degradation with a webserver using Xalan. On an intel dual-core machine it was 10 times slowdown than for a single processor intel machine. The problem occurs in this combination for the latest code: - Intel dual-processor - Sun JRE 5 Toadie's team was very capable and found that there was thread contention with synchronized methods, either Xalan-J code or in JRE classes such as java.util.Vector used by Xalan-J. This performance problem was so bad that thread contention just screamed at us, and made it easy to fine the "hot" synchronization spots. With their direction I changed Vector to the unsynchronized ArrayList in a number of locations got back most of the performance for them. Toadie previously let me know that a single processor did not have this problem, and recently checked that the IBM JRE 5 does not have the same synchronization performance problem on the dual-core machine. So heads up on Xalan's next multiprocessor performance problem. Hats off to Toadie who did a great job of analysis, providing hardware to do the analysis, and even the patches. - Brian Minchau mailto:[EMAIL PROTECTED]
