Re: [PATCH] Radix-tree pagecache for 2.5
Jeff Garzik (firstname.lastname@example.org)
Fri, 1 Feb 2002 14:47:51 -0500
On Fri, Feb 01, 2002 at 06:44:50PM +0000, email@example.com wrote:
> In article <20020201132953.A27508@havoc.gtf.org> you wrote:
> > On Fri, Feb 01, 2002 at 09:06:37AM -0800, Linus Torvalds wrote:
> >> Even databases often use multiple files, and quite frankly, a database
> >> that doesn't use mmap and doesn't try very hard to not cause extra system
> >> calls is going to be bad performance-wise _regardless_ of any page cache
> >> locking.
> > I've always thought that read(2) and write(2) would in the end wind up
> > faster than mmap(2)... Tests in my rewritten cp/rm/mv type utilities
> > seem to bear this out.
> the biggest reason for this is that we *suck* at readahead for mmap....
Is there not also fault overhead and similar issues related to mmap(2)
in general, that are not present with read(2)/write(2)?
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to firstname.lastname@example.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/