Messages in this thread | | | Date | Wed, 29 Jan 2003 10:00:11 -0800 | From | William Lee Irwin III <> | Subject | Re: no more MTRRs available ? |
| |
On Wed, Jan 29, 2003 at 09:20:01AM -0800, William Lee Irwin III wrote: >> Looks better than what I'm getting on 2.5.59: >> curly:~# cat /proc/mtrr >> reg00: base=0xc0000000 (49152MB), size=16384MB: uncachable, count=1 >> reg01: base=0x00000000 ( 0MB), size=524288MB: write-back, count=1 >> reg02: base=0x800000000 (524288MB), size=262144MB: write-back, count=1 >> Yes, this is standard ia32 (P-III/Coppermine cpus), and hence the >> numbers here are utter garbage.
On Wed, Jan 29, 2003 at 05:48:42PM +0000, Dave Jones wrote: > Bizarre. The size field isn't being shifted, and your base is somewhere > off in 64bit land. > See Andi's "RED-PEN" comments in various parts of arch/i386/kernel/cpu/mtrr/ > They need fixing at some point, and could be the cause of your problems.
OTOH since 0-512GB are in there this explains why the (massive) perf. decrease only happens sometimes. The MTRR corruption issues are only visible with 48GB atm. I haven't been focusing on MTRR's but I may arrange to trace the codepaths etc. in the eventual future to find where the bits are going bad esp. as benchmark time approaches.
-- wli - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |