Okay, I want to summarize my experience with kernel 2.6 now. I upgraded to the 2.6 final yesterday and ran some tests yesterday and all day today. First of all, kernel 2.6 worked fine, no crashes , all my drivers worked all my apps worked, all my hardware worked.
Test with overnet however revealed some issues, overnets CPU time usage is much higher with kernel 2.6. The first test I ran was overnet with glibc without nptl, overnet used about twice as much cpu time as before with kernel 2.4. For the second test I installed linux-headers 2.6-beta11 and compiled glibc with nptl (use flag nptl was set), the result stayed the same. So overnet used about 15-20% cpu time with kernel 2.6 , with 2.4 it was around 5-10% . To be able to compare the two results I ran the tests for hours and compared the cpu time whenever overnet build up aproximately the same number of tcp connections(measured with netstat) and the same number of openfiles(measured with lsof). Another effect: After compiling in nptl I noticed, that top gets confused by nptl the values it shows are not correct anymore. For example while compiling the accumulated cpu time is 90% but the compile process cc1 shows that it is using 2-5% cpu time and all other processes show about 0%, cc1 normally is around 90% while compiling, I upgraded procps to the latest release because top belongs to procps, but that didn't help it. So top is not working corectly with nptl. Although the system seems very responsive now I think something is wrong with 2.6 I'm not really sure what causes this, it could be due to the new TCP Stack, a result of the new sheduling, or thread handling. Who knows??? I would love to see a discussion about that and maybe some other tests with other applications, for example a webserver or database server under high load. Gr��e Stefan -- [EMAIL PROTECTED] mailing list
