[lkml]   [2007]   [May]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [rfc] increase struct page size?!
On Fri, 18 May 2007, Nick Piggin wrote:

> However we don't have to let those 8 bytes go to waste: we can use them
> to store the virtual address of the page, which kind of makes sense for
> 64-bit, because they can likely to use complicated memory models.

That is not a valid consideration anymore. There is virtual memmap update
pending with the sparsemem folks that will simplify things.

> Many batch operations on struct page are completely random, and as such, I
> think it is better if each struct page fits completely into a single
> cacheline even if it means being slightly larger.

Right. That would simplify the calculations.

> Don't let this space go to waste though, we can use page->virtual in order
> to optimise page_address operations.

page->virtual is a benefit if the page is cache hot. Otherwise it may
cause a useless lookup.

I wonder if there are other uses for the free space?

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2007-05-18 20:19    [W:0.214 / U:2.028 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site