[PATCH] disable addres space randomization default on transmeta CPUs

We know that the randomisation slows down some workloads on Transmeta CPUs
by quite large amounts.  We think it's because the CPU needs to recode the
same x86 instructions when they pop up at a different virtual address after
a fork+exec.

So disable randomization by default on those CPUs.

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Eric Lammerts 2005-07-31 22:34:42 -07:00 committed by Linus Torvalds
parent 3fef3fa24d
commit cdf32eaa4e
1 changed files with 4 additions and 0 deletions

View File

@ -76,6 +76,10 @@ static void __init init_transmeta(struct cpuinfo_x86 *c)
#define USER686 (X86_FEATURE_TSC|X86_FEATURE_CX8|X86_FEATURE_CMOV)
if ( c->x86 == 5 && (c->x86_capability[0] & USER686) == USER686 )
c->x86 = 6;
/* randomize_va_space slows us down enormously;
it probably triggers retranslation of x86->native bytecode */
randomize_va_space = 0;
}
static void transmeta_identify(struct cpuinfo_x86 * c)