[ILUG] [Fwd: 10.31 second kernel compile]

[Padraig Brady]

This is getting ridiculous...

-------- Original Message --------
Subject: 10.31 second kernel compile
Date: Wed, 13 Mar 2002 19:52:17 +1100
From: Anton Blanchard <anton at samba.org>
To: lse-tech at lists.sourceforge.net
CC: linux-kernel at vger.kernel.org

Let the kernel compile benchmarks continue!

hardware: 24 way logical partition, 1.1GHz POWER4, 60G RAM

kernel: 2.5.6 + ppc64 pagetable rework

kernel compiled: 2.4.18 x86 with Martin's config

compiler: gcc 2.95.3 x86 cross compiler


# MAKE="make -j14" /usr/bin/time make -j14 bzImage
...
make[1]: Leaving directory `/home/anton/intel_kernel/linux/arch/i386/boot'
130.63user 71.31system 0:10.31elapsed 1957%CPU (0avgtext+0avgdata 
0maxresident)k


Due to the final link and compress stage, there is a fair amount of idle
time at the end of the run. Its going to be hard to push that number
lower by adding cpus.

The profile results below show that kernel time is dominated by the low
level ppc64 pagetable management. We are working to correct this, a lot
of the overhead in __hash_page should be gone soon. The rest of the
profile looks pretty good, do_anonymous_page and lru_cache_add show
up high as they did in Martin's results.

Thanks to Milton Miller who helped with the benchmarking, and the ppc64
team!

Anton
--
anton at samba.org
anton at au.ibm.com

[snip]