User's Guide

Commands: Log Sense (4Dh) Page 71
Data Compression Transfer Log Page (Page 39)
Page 39, the Data Compression Transfer Log Page, allows you to monitor the
performance of data compression.
The Data Compression Page Parameter Codes are given in the following table:
Name Code Length Description
Number of
entities written
Number
0001h 8 The total number of complete entities written to or read
from the tape since the last power-on or Clear Log
operation
Number of
entities read
0002h 8
Number of
records written
0003h 8 The total number of records (both compressed and
uncompressed) written to or read from the tape since the
last power-on or Clear Log operation.
Number of
records read
0004h 8
Kilobytes to data
compression
0005h 8 The total number of kilobytes written to or read from the
tape since the last power-on or Clear Log operation. When
reading this number may be greater than the number
transferred to the host due to read ahead.
Kilobytes from
data compression
0006h 8
Kilobytes to tape 0007h 8 The total number of kilobytes written to or read from the
tape since the last power-on or Clear Log operation
Kilobytes from
tape
0008h 8
Logical entity size 0009h 8 The logical size of the last entity written to or read from
tape (size = number of records in entity X record size)
Physical entity
size
000Ah 8 The physical size of the last entity written to or read from
the tape. (size = entity header length X uncompressed
data length)
Uncompressed
entities
000Bh 8 The total number of times a non-compressed entity has
been encountered on the tape during a read operation
since the last power-on or Clear Log operation
Drive Configuration Information Page (Page 3A)
Parameter Code Length Name
01
4
Raw switch settings
02 4 Compression enabled set by mode select
03 4 Decompression enabled set by mode select
04 4 Block size used for writing
05 4 Current partition
06 4 Prevent (1) or allow (0) media removal
07 4 Cartridge write protected
08 4 Report setmarks
09 4 Data compression ratio
Drive Usage Information Page (Page 3C)
Parameter Code Length Name
01
8
Total groups written
02 8 Total rewrites
03 8 Total groups read
04 8 Total ecc c3 corrections
05 8 Total rereads
06 3 Total load count