FC4 kernel performance

[Malita, Florin]

On Tue, 2005-06-21 at 11:47 -0400, Dave Jones wrote:
> Which is an apples to oranges comparison. 2.6.11-1.1369_FC4 is 
> actually based on 2.6.12rc6.  I'll be interested in seeing results 
> rerun against this kernel.

Back with some apples: http://lufs.sourceforge.net/unixbench.html

Now I have:

1. Linux 2.6.12-rc6 (nodebug+p4+nose+nohm+lean): 355.7
2. Linux 2.6.11.12 (nodebug+p4+nose+nohm+lean): 345.8 
3. Linux 2.6.11-1.1369_FC4 (nodebug+p4+nose+nohm+lean): 269.3 
4. Linux 2.6.11-1.1369_FC4 (nodebug+p4+nose+ nohm): 253.1 
5. Linux 2.6.11-1.1369_FC4 (nodebug+p4): 239.4 
6. Linux 2.6.11-1.1369_FC4 (nodebug): 236.7 
7: Linux 2.6.11-1.1369_FC4 (orig): 213.2 
8: SunOS 5.11 (orig): 122.3 

(1, 2 & 3 here share the same configuration)

So 2.6.12-rc6 is slightly better overall than 2.6.11.12 and still a lot
faster than FC4 (especially in the syscall overhead & pipe throughput
area).

Am I correct in assuming the FC kernel doesn't use the vsyscall/sysenter
mechanism thus taking a serious performance hit on P4s?

Regards,
Florin