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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.


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.


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