User: Password:
|
|
Subscribe / Log in / New account

Speeding up the page allocator

Speeding up the page allocator

Posted Feb 27, 2009 1:08 UTC (Fri) by jzbiciak (subscriber, #5246)
In reply to: Speeding up the page allocator by jzbiciak
Parent article: Speeding up the page allocator

Ah, it appears AMD K7 and beyond go one better and have a "streaming store" that doesn't even do a cache allocate. Nice.

Here's the MMX and AMD optimized copies and fills the kernel currently uses. I can't imagine they'd settle for a crappy loop here, and it looks like some thought was put into these.

http://lxr.linux.no/linux+v2.6.28.7/arch/x86/lib/mmx_32.c

On regular x86, they do indeed use "rep stosl". (I guess the AT&T syntax spells it "stosl" instead of "stosd"?) See around like 92.

http://lxr.linux.no/linux+v2.6.28.7/arch/x86/include/asm/...

Rampant speculation is fun and all, but I suspect Arjan actually measured these. :-) (Or, at least the ones in the MMX file.)


(Log in to post comments)


Copyright © 2017, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds