[lkml]   [2003]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Subjectobject-based rmap and pte-highmem
> So whole stole the remaining 1.85 seconds?   Looks like pte_highmem.

I have a plan for that (UKVA) ... we reserve a per-process area with
kernel type protections (either at the top of user space, changing
permissions appropriately, or inside kernel space, changing per-process
vs global appropriately).

This area is permanently mapped into each process, so that there's no
kmap_atomic / tlb_flush_one overhead ... it's highmem backed still.
In order to do fork efficiently, we may need space for 2 sets of
pagetables (12Mb on PAE).

Dave McCracken had an earlier implementation of that, but we never saw
an improvement (quite possibly because the fork double-space wasn't
there) - Dave Hansen is now trying to get something work with current
kernels ... will let you know.


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: 2005-03-22 13:33    [W:0.282 / U:0.612 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site