Re: [PATCH 00/33] Adaptive read-ahead V12

Andi Kleen
2006-05-26T14:00:22Z

Andrew Morton <akpm@osdl.org> writes:
>
> These are nice-looking numbers, but one wonders. If optimising readahead
> makes this much difference to postgresql performance then postgresql should
> be doing the readahead itself, rather than relying upon the kernel's
> ability to guess what the application will be doing in the future. Because
> surely the database can do a better job of that than the kernel.

With that argument we should remove all readahead from the kernel?
Because it's already trying to guess what the application will do.

I suspect it's better to have good readahead code in the kernel
than in a zillion application.

-Andi