[lkml]   [2009]   [Mar]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [patch 2/3] slub: scan partial list for free slabs when thrashing
    On Mon, 30 Mar 2009, Christoph Lameter wrote:

    > > Whenever a cpu cache satisfies a fastpath allocation, a fastpath counter
    > > is incrememted. This counter is cleared whenever the slowpath is
    > > invoked. This tracks how many fastpath allocations the cpu slab has
    > > fulfilled before it must be refilled.
    > That adds fastpath overhead and it shows for small objects in your tests.

    Indeed, which is unavoidable in this case. The only other way of tracking
    the "thrashing history" I can think of would be bitshifting a 1 for
    slowpath and 0 for fastpath, for example, into an unsigned long. That,
    however, requires a hamming weight calculation in the slowpath and doesn't
    scale nearly as well as simply an incrementing a counter.

    If there's other approaches on tracking such instances, I'd be interested
    to hear them.

    Btw, is your new email address or are all emails going to eventually migrate to the new domain?

     \ /
      Last update: 2009-03-30 22:27    [W:0.019 / U:17.124 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site