On Nov 12, 2007 7:42 PM, Christoph Lameter <[email protected]> wrote:
> Ok here is the patch to remove DISCONTIG and FLATMEM
>
> x86_64: Make sparsemem/vmemmap the default memory model
>
> Use sparsemem as the only memory model for UP, SMP and NUMA.
> Measurements indicate that DISCONTIGMEM has a higher overhead
> than sparsemem. And FLATMEMs benefits are minimal. So I think its
> best to simply standardize on sparsemem.
>
> Results of page allocator tests (test can be had via git from slab git
> tree branch tests)
>
> Measurements in cycle counts. 1000 allocations were performed and then the
> average cycle count was calculated.
>
> Order FlatMem Discontig SparseMem
> 0 639 665 641
> 1 567 647 593
> 2 679 774 692
> 3 763 967 781
> 4 961 1501 962
> 5 1356 2344 1392
> 6 2224 3982 2336
> 7 4869 7225 5074
> 8 12500 14048 12732
> 9 27926 28223 28165
> 10 58578 58714 58682
Discontig obviously needs to die. However, FlatMem is consistently
faster, averaging about 2.1% better overall for your numbers above. Is
the page allocator not, erm, a fast path, where that matters?
Order Flat Sparse % diff
0 639 641 0.3
1 567 593 4.4
2 679 692 1.9
3 763 781 2.3
4 961 962 0.1
5 1356 1392 2.6
6 2224 2336 4.8
7 4869 5074 4.0
8 12500 12732 1.8
9 27926 28165 0.8
10 58578 58682 0.2
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
