I have been looking at a possible issue in recent months where the PLE drops (sometimes to below 200) for prolonged periods - it can be as high as 60,000.
Further to this, we now seem to have an issue with the Buffer Pool reducing in size over time (started at 116GB now 80GB) which suggests to me that we
likely have additional Memory pressure (further impacting PLE).
I am getting a handle on the above, but there is something that I do not understand.
As a result of the above 2 factors, I expected to see a large drop in the Buffer Cache Hit Ratio reported by DPA -but the value rarely chnges.
DPA reports 99% most of the time, and the lowest value I can ever find reported is 96%.
Does this make sense - i.e. am I misunderstanding something here?
Steve O.