I thought that it might be helpful to provide several brief comments about the summary I/O operation performance metrics shown within Ao1's prior post #201, where he compared file transfer speeds between TeraCopy and Windows Explorer.

Basically, the summary metrics (which were collected upon a periodic basis for each of the respective files) displayed by the hIOmon Presentation Client for the overall summary metrics reflect the combined total of the opened "instances" of the file, whereas the displayed tabular metrics (presumably from the CSV-formatted hIOmon Manager Export File) reflect a separate row for each opened instance of the respective file (which is why there are sometimes multiple entries for the same file within the displayed tables, with each entry for the same file basically representing a separate "instance" of the file).

So what's an "instance" of a file? The hIOmon software can optionally collect and maintain summary I/O operation performance metrics upon an individual specific file, device, and/or process basis.

In the case of files, it is possible that a given file will be concurrently accessed by, for example, more than one process (e.g., Windows Explorer, the System process, and/or an AntiVirus program).

Normally upon "opening" the file, each such process will receive a "file handle", which essentially represents its particular open "instance" of the same file. Accordingly, the hIOmon software collects and maintains separate summary I/O operation performance metrics for each such separate "instance", with these summary metrics reflecting the monitored I/O operations directed towards the respective instance of the file. (Please note that the hIOmon software also maintains some summary metrics upon an overall file basis, i.e., regardless of the particular instance of the file).

As a second comment, Ao1 is correct about the Windows Explorer file copy operation involving the system file cache. In particular, the hIOmon Presentation Client display illustrates that the data to be copied was written to the system file cache (q.v., the write "SystemCache" data transfer amount), then transferred to the device proper (q.v., the overall amount of data written was twice the size of the "TEST file.mpg" file). This is in accordance with the information Ao1 presented in his post #203

As a third comment, the sum of the random I/O operation count and the sequential I/O operation count will be one less than the associated reported total I/O operation count for the respective file/device (since the first I/O operation to the file/device is considered to be neither a random nor a sequential I/O operation). In turn, the sum of the random data transferred amount and the sequential data transferred amount will be less than the total data transferred amount (i.e., the data transferred by the first I/O operation to the file/device is likewise considered to be neither random or sequential data transferred).

Lastly, the hIOmon software presents its throughput metrics in terms of MB/s (i.e., megabytes-per-second, with one megabyte = 1 000 000 bytes) rather than MiB/s (i.e., mebibytes-per-second, with one mebibyte = 1 048 576 bytes).