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Bug #18514

Wall-time is sensitive to tick rate in VxWorks 6.4 kernels targeting 2400s

Added by Richard Neswold almost 2 years ago. Updated over 1 year ago.

Status:
Assigned
Priority:
High
Category:
VxWorks 6.4 / MVME-2401
Start date:
12/08/2017
Due date:
% Done:

0%

Estimated time:
Duration:

Description

Duane Voy reports:

Does any of the MOOC, ACNet, etc. code that we users load for normal front-end operation use the following?

struct timespec ts;
clock_gettime( CLOCK_REALTIME, &ts );

I have found another issue in the VxWorks kernel that we use in the Delivery Ring front-ends. When I set the system clock rate faster than the default 100 ticks per second, the time value returned by the above code speeds up proportionally. So in my case changing from the default 100 Hz to 500 results in time appearing to pass 5 times faster than reality!

I can imagine this having subtle effects in the control system software. Could this cause the network address tables being flushed without explanation for example?

He also provided evidence that it's used extensively throughout our products.

History

#1 Updated by Richard Neswold almost 2 years ago

  • Subject changed from Clock to Wall-time is sensitive to tick rate in VxWorks 6.4 kernels targeting 2400s

Hmmm. The subject line lost some text.

#2 Updated by Richard Neswold over 1 year ago

  • Category set to VxWorks 6.4 / MVME-2401


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