#6053 HIGH 9.1.0: Clock drift during suspend/resume.

[Zarro Boogs per Child]

#6053: Clock drift during suspend/resume.
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           Reporter:  cscott     |       Owner:  JordanCrouse
               Type:  defect     |      Status:  new         
           Priority:  high       |   Milestone:  9.1.0       
          Component:  kernel     |     Version:              
         Resolution:             |    Keywords:              
        Next_action:  never set  |    Verified:  0           
Deployment_affected:             |   Blockedby:              
           Blocking:  4606       |  
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Comment(by JordanCrouse):

 While that is a clever idea, consider the following handy table:

 ||Divisor||Max Seconds||Granularity||
 ||1||2.000||3.0517578125E-05||
 ||2||4.000||6.103515625E-05||
 ||4||8.000||0.0001220703125||
 ||8||16.000||0.000244140625||
 ||16||32.000||0.00048828125||
 ||32||63.999||0.0009765625||
 ||64||127.998||0.001953125||
 ||128||255.996||0.00390625||
 ||256||511.992||0.0078125||
 ||512||1023.984||0.015625||
 ||1024||2047.969||0.03125||
 ||2048||4095.938||0.0625||
 ||4096||8191.875||0.125||
 ||8192||16383.750||0.25||
 ||16384||32767.500||0.5||
 ||32768||65535.000||1||

 We can get over 18 hours of time tracking at the highest divisor, but we
 won't be able to do any better then second resolutions, which is no better
 then we have now.  Cutting the precision down to a more reasonable 250
 milliseconds will only give us a little bit more then two hours of
 tracking before the counter will roll.  I think that is too little time
 for this to be a reliable replacement for the RTC.

-- 
Ticket URL: <http://dev.laptop.org/ticket/6053#comment:8>
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