|Overall Statistics||WinRAR: Compressing|
|Data Read||1.51 MB|
|Data Written||5.60 MB|
|Disk Busy Time||0.03 s|
|Average Data Rate||213.55 MB/s|
When you compress data, you're essentially taking multiple files and assembling them into a single file that occupies less space. As a result, you might assume that this task would consist of sequential accesses. The opposite actually turns out to be true.
Why is this? All forms of data compression replace repeated occurrences of data with references to a single copy of that data existing earlier in the input (uncompressed) data stream.
Consequently, compression turns out to be mostly a random write-heavy operation. However, the amount of data the system reads and writes is greater than the sum of the uncompressed (~400 KB) and compressed files (1 MB).
- 58% of all operations occur at a queue depth of one
- 37% of all operations occur between a queue depth of two and eight
- 11% of all data transferred is sequential
- 12% of all operations are sequential
- 29% of all operations are 4 KB in transfer size
- 32% of all operations are 32 KB in transfer size
- 14% of all operations are 128 KB in transfer size
- 13% of all operations are 16 KB in transfer size