Re: [PATCH] Scalable page cache - take two

[William Lee Irwin III <wli@holomorphy.com>]

On Mon, Dec 24, 2001 at 12:15:33AM +0200, Momchil Velikov wrote:
> This is the second mutation of the scalable page cache patch.  It:
> 
>         - removes the global page cache hash table and the associated lock
> 
> 	- implements the page cache as a per mapping radix tree. This
>           increases the size of ``struct inode'' by 8 bytes (in 32bit
>           ports).  The branch factor is a compile time constant
>           ``RAD_MAP_SHIFT'' (currently 7, 128 pointers)
> 
>         - decreases the size of ``struct page'' by removing
>           ``next_hash'' and ``pprev_hash' fields as they are no longer
>           needed for the page cache.  NOTE that this curently breaks
>           sparc64 and arm ports. The sparc64 port is trivialy fixable.
> 
> The patch is stable on UP (survives make -j6) and does not have
> noticeable performance impact (at least for the kernel compile
> benchmark) in either direction.

Beautiful programming!


Cheers,
Bill