PERF_COUNTER_LARGE_QUEUELEN_TYPE

Description This counter type monitors the average length of a queue to a resource over time. Counters of this type display the difference between the queue lengths observed during the last two sample intervals, divided by the duration of the interval. This counter type is the same as PERF_COUNTER_QUEUELEN_TYPE except that it uses larger fields to accommodate larger values.
Generic type Average
Formula (N1 - N0) / (D1 - D0), where the numerator (N) represents the number of items in a queue and the denominator (D) represents the time elapsed during the sample interval.
Average (Nx - N0) / (Dx - D0)
Example PhysicalDisk\ Avg. Disk Queue Length

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