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Resilience an Important Schedule Quality Attribute

4 replies [Last post]
Fri, 2017-12-01 13:51
Colin Peters
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Here we look at why resilience is a more important schedule quality than critical path optimization http://ed.gr/iuji

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Sat, 2017-12-02 17:35
#1
Vladimir Liberzon
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Mike,

I did not expect such statement from you.

Schedule optimization always leads to minimizing activity floats.

Crashing leads to parallel paths with minimal floats.

Best Regards,

Vladimir

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Sun, 2017-12-03 13:17
#2
Rafael Davila
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To say resilience is a more important schedule quality than critical path optimization is in error.

  • You get a higher increase in probabilities of success by targeting critical path.
  • Critical path optimization is the most important factor to address, to say otherwise is misleading.
  • I do not mean to say to say near critical paths do not matter, merge bias do matter. The point is that critical path is still the most important path to increase probabilities of success.
  • It cost less to compress a single path than many.
  • 85% success probability is considered a pragmatic target.
  • Crashing might come at a very high cost, crashing of non critical paths makes not much sense. 

The following figure compares different strategies, in most cases if you want to increase the probabilities instead of compressing parallel paths it will be better to further compress the current critical path.
  

Resilient_Schedule

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Sat, 2017-12-02 15:51
#3
Mike Testro
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Hi Vladimir.

More than 1 critical path means that the logic has been rigged to create them.

Best regards

Mike T.

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Fri, 2017-12-01 21:09
#4
Vladimir Liberzon
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I wonder who may support an idea that longer schedule with one critical path is better than shorter schedule that has several critical or subcritical paths.

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