Hello, we recently did SPECpower benchmark measurements on a 2xQuad-Core Harpertown (Intel E5440) Server and found that the results were generally slightly better under Windows than under Linux, despite Linux technology like the tickless kernel. The reason was twofold:
1 The raw performance value under Windows is 1-2% better. This seems to be a matter of optimization of the JVM used (BEA), not a lot we can do about it. 2 The power consumption under Linux at 100% and 0% load is approx. the same as under Windows. But in the intermediate levels 50%-10%, Windows is roughly 3-5W better (increasing towards lower load levels). This suggests that Windows power management is more aggressive than Linux. Is there a description somewhere how to modify cpuidle governor tunables? The kernel used was Fedora Rawhide 2.6.24-fc9 (x86_64). We are about to upgrade to an even more recent kernel. The "menu" cpuidle governor was used. For those who don't know the SPECpower benchmark: It uses a Java-based database-type load which runs entirely in system memory (no disk IO). First a maximum load is calibrated. After that, the load is reduced in steps of 10%. A final "active idle" measurement has the JVM loaded, but no requests. We'd be thankful for any suggestions wrt choice of the kernel, tunables, and other hints, which hel us to improve the Linux results. Martin -- Martin Wilck PRIMERGY System Software Engineer FSC IP ESP DE6 Fujitsu Siemens Computers GmbH Heinz-Nixdorf-Ring 1 33106 Paderborn Germany Tel: ++49 5251 8 15113 Fax: ++49 5251 8 20209 Email: mailto:[EMAIL PROTECTED] Internet: http://www.fujitsu-siemens.com Company Details: http://www.fujitsu-siemens.com/imprint.html _______________________________________________ Discuss mailing list [email protected] http://mail.lesswatts.org/mailman/listinfo/discuss
