Uninformed: Informative Information for the Uninformed

Vol 7» 2007.May

Tick Count

The tick count was accurately calculated 67 percent of the time (3396 times). The reason for this lower rate of success is due in large part to the fact that the tick count is calculated in relation to the estimated system time value. As such, if an incorrect system time value is determined, the tick count itself will be directly influenced. This should account for at least 23 percent of the inaccuracies judging from how often the system time was inaccurately estimated. The remaining 10 percent of the inaccuracies is as of yet undetermined, but it is most likely related to the an improper interpretation of the constant scaling factor that is applied to the tick count. In any case, it is expected that only a few bits are actually affected in the remaining 10 percent of cases.

Figure 5.6: Percent accuracy of each bit position for the estimated Tick Count
Image ds_tickcount_bits