[lkml]   [2002]   [Jun]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: gettimeofday problem
    On 2000000 call -> 189 times I found the problem (0.00945%)
    On 20000000 call ->1956 found I found the problem (0.00978%)

    Probably you're right my previous percentage is too high (the one above
    should be the correct one).

    But do you think that this behaviour is normal?

    Matti Aarnio wrote:

    >On Mon, Jun 24, 2002 at 12:20:02PM +0200, Salvatore D'Angelo wrote:
    >>In this piece of code I convert seconds and microseconds in
    >>milliseconds. I think the problem is not in my code, in fact I wrote the
    >>following piece of code in Java, and it does not work too. In the for
    >>loop the 90% of times b > a while for 10% of times not.
    >> long a = System.currentTimeMillis();
    >> long b = System.currentTimeMillis();
    >> if (a > b) {
    >> System.out.println("Wrong!!!!!!!!!!!!!");
    >> }
    > So in 10% of the cases, two successive calls yield time
    > rolling BACK ?
    > I used gettimeofday() call, and compared the original data
    > from the code.
    > At a modern uniprocessor machine I never get anything except
    > monotonously increasing time (TSC is used in betwen timer ticks
    > to supply time increase.) At a dual processor machine, on
    > occasion I do get SAME value twice. I have never seen time
    > rolling backwards.
    > Uh.. correction: 216199245 0:-1 -- it did step backwards,
    > but only once within about 216 million gettimeofday() calls.
    > (I am running 2.4.19-pre8smp at the test box.)
    >/Matti Aarnio
    >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

    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 13:27    [W:0.024 / U:1.368 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site