Re: to show that RTLinux is faster than Linux



amitbhat555@xxxxxxxxx wrote:

hi i'm doing a project which requires to prove practically that RTLinux
is faster than Linux ..
can any one help me in this matter.

It isn't faster. But it's predictable, you get a guaranteed
response within a specified time.

Last time I run such a test (kernel version 2.4.9), I measured
interrupt latency by using a fast counter on a custom PCI board.
It turned out that the interrupt latency on an unloaded linux
system was shorter by a factor of 2 compared to RTLinux on the
same setup.

However, as soon as the system load increased, I measured interrupt
latencies as bad a 0.5 seconds. The main culprit turned out to be
a SCSI driver which sometimes disabled interrupts for that length
of time.

In the same situation, the RTLinux interrupt latency stayed unchanged.

Kind regards,

Iwo

.



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