I want to get a buffer hit ration based on deltas. Actually it would have to be from normalised deltas. The question is this possible and how? If not it should be an improvement to the system. For example the buffer hit information is based on total time but one may have made changes that affect the buffer hit ratio and the only way to see is reseting the counters.
If you need to modify the area, I it may be nice to have the sum over a period of time. For example, you may be refreshing every 15 seconds but you want the hit ratio to reflect the last running 10 minutes. Looking at the logic I can't see this being easy. May be a weighted average would give the desired result. This can be readily done on a running average which is how the average is being calculated. Thus a buffer hit ratio could be calculated from the weighted average which gives a picture over an extended period of time with emphasis on the performance latest history.