[lkml]   [2007]   [Feb]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [RFC 0/8] Cpuset aware writeback
    On Thursday February 1, wrote:
    > The NFS problems also exist for non cpuset scenarios
    > and we have by and large been able to live with it so I think they are
    > lower priority. It seems that the basic problem is created by the dirty
    > ratios in a cpuset.

    Some of our customers haven't been able to live with it. I'm really
    glad this will soon be fixed in mainline as it means our somewhat less
    elegant fix in SLES can go away :-)

    > BTW the block layer also may be layered with raid and stuff and then we
    > have similar issues. There is no general way so far of handling these
    > situations except by twiddling around with min_free_kbytes praying 5 Hail
    > Mary's and trying again.

    md/raid doesn't cause any problems here. It preallocates enough to be
    sure that it can always make forward progress. In general the entire
    block layer from generic_make_request down can always successfully
    write a block out in a reasonable amount of time without requiring
    kmalloc to succeed (with obvious exceptions like loop and nbd which go
    back up to a higher layer).

    The network stack is of course a different (much harder) problem.

    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: 2007-02-02 07:05    [W:0.040 / U:16.872 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site