Re: Time::HiRes usleep on windows strange behaviour...please please help!!

mastermagrath wrote:

> what confuses me is what is the point in
> having high res functions when you say that a rounding of 1/100sec
> ticks is expected?!!
> How then do programmers generally control loops to finer timeslices,
> i'm sure it must be quite common to accurately control the frequency of
> iteration of loops to a finer frequency than 1/100??

Your timer resolution will be equal to the time duration between system ticks.
This is a value directly dependent on system load; higher load, less accuracy.

On the average, your maximum resolution will be ten milliseconds.

However, for NT4 and NT5 system types, you can install a hyper-kernel
which preempts default system interrupts allowing resolution down to
ten microseconds for an old Pentium running at 133 mHz.

Modern NT systems, such as my dual processor machine, can reach
a resolution of three to five microseconds.

If you are interesting in timing packets, use configurable ping software
such as WS_Pro PingPack. Resolution for WS Ping is as low as
one millisecond, and sometimes reports zero milliseconds.

MSDOS Ping will report speeds less than ten milliseconds, when
pinging a very fast host or your localhost, but that report will
read < 10 milliseconds by default.

Rather pointless to pursue faster speeds for internet transaction
packets. Your speed will be that of the slowest gateway, not
your system.

Purl Gurl
.

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