On Wed, Apr 06, 2005 at 07:06:17AM -0400, Alan Cox wrote:
On Tue, Apr 05, 2005 at 11:53:33AM -0700, Jeffrey Buell wrote:
> results are pretty ugly compared to a 2.6.1 install. FC4 ranges from 1.5X to
> 20X slower, while xen0 is about 2X to 6X slower. Is this expected? I'm
> looking for configuration differences now, but I'm wondering if anybody can
The fork ones are expected yes. The newest kernels have four level page tables
and while this allows for huge 64bit systems it has a cost and there is
optimisation work left to do.
They should be getting collapsed away back to 2/3-level PTEs by the compiler
in the current builds. I thought that got fixed for 2.6.12-rc1.
If it missed it, theres a .12-rc2 update pending, but that won't hit
until post -test2 now.
I've not checked the kernel config options but if you look at the
can see what debug is enabled
Slab debug is the only thing left on thats really a performance hit.