lkml.org 
[lkml]   [2004]   [Oct]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Date
    SubjectRe: [patch rfc] towards supporting O_NONBLOCK on regular files
    ==> Regarding Re: [patch rfc] towards supporting O_NONBLOCK on regular files; "Stephen C. Tweedie" <sct@redhat.com> adds:

    sct> Hi, On Thu, 2004-10-07 at 11:12, Marcelo Tosatti wrote:

    >> Oh yes, theres also the indirect blocks which we might need to read from
    >> disk.

    sct> Right.

    >> Now the question is, how strict should the O_NONBLOCK implementation be
    >> in reference to "not blocking" ?

    sct> Well, I suspect that depends on the application. But if you've got an
    sct> app that really wants to make sure its hot path is as fast as possible
    sct> (eg. a high-throughput server multiplexing disk IO and networking
    sct> through a single event loop), then ideally the app would want to punt
    sct> any blocking disk IO to another thread.

    sct> So it's a matter of significant extra programing for a small extra
    sct> reduction in app blocking potential.

    sct> I think it's worth getting this right in the long term, though.
    sct> Getting readahead of indirect blocks right has other benefits too ---
    sct> eg. we may be able to fix the situation where we end up trying to read
    sct> indirect blocks before we've even submitted the IO for the previous
    sct> data blocks, breaking the IO pipeline ordering.

    So for the short term, are you an advocate of the patch posted?

    -Jeff
    -
    To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
    the body of a message to majordomo@vger.kernel.org
    More majordomo info at http://vger.kernel.org/majordomo-info.html
    Please read the FAQ at http://www.tux.org/lkml/

    \
     
     \ /
      Last update: 2005-03-22 14:06    [W:2.292 / U:0.204 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site