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    SubjectRe: Higher than expected disk write(2) latency
    David Newall wrote:
    > Martin Lucina wrote:
    >> Measurement of the write(2) time is performed using the TSC, so any
    >> latency there is negligible.
    >
    > Measuring each write is lavish and bound to impact the results. To
    > measure sustained throughput, get the time only at start and end, and
    > divide the difference by the number of writes.

    Hi,

    We're using RDTSC to measure time, which takes ~30 nanoseconds to
    complete. I would say this is negligible given that latency of a write
    is 5 orders of magnitude higher.

    Martin



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