Suggestions on Avoiding syscall Overhead

Dag-Erling Smørgrav des at
Mon Apr 30 20:42:22 UTC 2007

Robert Watson <rwatson at> writes:
> Unfortunately, this sort of thing can't be expressed using the
> standard APIs. This leaves us two choices: allow the behavior of
> standard APIs to be configured at some granularity, or introduce new
> APIs.  My feeling is we should prefer new APIs, and suggest that
> programmers use those.  Take a look at sys/sys/time.h:1.71 for an
> example of what might make sense.

I'm not sure this is a good example.

There is already a suitable extensible API: clock_gettime(), which is
part of SUSv3.  Define new CLOCK_* constants for requesting a faster,
less precise timecounter, and if you feel like it, submit it to X/Open
for inclusion in the next version of the SUS.

Dag-Erling Smørgrav - des at

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