70 Commands
Data Compression Log Page
The Data Compression Log Page code is 32h and the page length is 4Ch.
There are ten parameters, 0 through 9. Parameters 0 and 1 are two bytes long.
Parameters 2 through 9 are each 4 bytes long.
The supported fields are listed below. Parameters 2 through 9 occur as pairs
that represent a large number of bytes transferred. The first four-byte
parameter represents the number of whole megabytes transferred, rounded to
the nearest megabyte. The second four-byte parameter represents the
difference between this number of megabytes and the actual number of bytes.
This may be a signed quantity.
This data may be reset, but may not be written.
Performance Data Log Page
The Performance Data Log Page is 34h. This log is intended to report data of
interest to a user/application on how efficiently the drive is being used.
Parameter Description Length
0 Read compression ratio X 100
2
1 Write compression ratio X 100
2
2 Megabytes transferred to host
4
3 Bytes transferred to host
4
4 Megabytes read from tape
4
5 Bytes read from tape
4
6 Megabytes transferred from host
4
7 Bytes transferred from host
4
8 Megabytes written to tape
4
9 Bytes written to tape
4
Parameter Description Length Updated
0 Repositions per 100 MB 2 After each 100 MB has been physically written
1 Data rate into buffer 2 After each data set has been logically written
