Re: [PATCH] small sym-2 fix

Hugh Dickins
2001-11-15T21:21:29Z

On Thu, 15 Nov 2001, Gérard Roudier wrote:
>
> To be serious, the right fix is to have some logical page be some power of
> two of the physical page when the physical page is too small. Can we hope
> Linux-2.5 to allow this?

It's certainly doable. I have an i386 patch against 2.4.7 which did that,
MMUPAGE_SIZE 4kB distinguished from PAGE_SIZE 4kB, 8kB, 16kB or 32kB
(but 64kB truncates to 0 in unsigned short b_size, doesn't work so well!);
while still presenting the 4kB EXEC_PAGESIZE to userspace.

It's a bit tedious working through each kernel update, to decide which
PAGEs should be MMUPAGEs etc, and I didn't see an immediate reward of
a huge leap in performance, so I haven't kept it up to date since then.

Hugh