When operating in a host environment where the net host data rate is less than the
maximum drive native data rate, the TS1130 tape drive and TS1120 tape drive
automatically perform dynamic speed matching to minimize backhitches. Dynamic
speed matching adjusts the native data rate of the drive as closely as possible to the
net host data rate (after data compressibility has been factored out). A reduction in
backhitches improves system performance.
High resolution tape directory (HRTD)
This directory structure, located in the TS1130 tape drive and TS1120 tape drive,
allows the drive to have fast and consistent nominal and average access times for
Locate operations.
Channel calibration and on-the-fly adaptive equalization
To gain optimum performance, channel calibration allows the drive to automatically
customize each read and write data channel. The customization compensates for
variations in the recording channel transfer function, for media characteristics, and
for read and write head characteristics. Initial calibration settings are calculated and
stored at the time of manufacture. For optimum error rate performance, the TS1130
tape drive and TS1120 tape drive also use on-the-fly adaptive equalization hardware
on an ongoing basis to adjust the read equalization response.
Recursive accumulating backhitchless flush
The TS1130 tape drive and TS1120 tape drive use an algorithm known as recursive
accumulating backhitchless flush (or non-volatile caching) to increase effective data
rate performance from host servers that force explicit Synchronize operations during
Write operations.
Backhitchless backspace
Backhitchless backspacing enables some backspace operations to be virtualized
without physical backhitching. If you write and overwrite multiple trailer labels, this
firmware feature provides major performance improvements. For more information,
refer to the appendix about WORM behavior in the
IBM System Storage™ 3592 Tape
Drive SCSI Reference
.
Capacity scaling
If you want to exchange capacity for improved access times, the TS1130 tape drive
and TS1120 tape drive support multiple format options, such as scaling and
segmentation modes. The TS1130 tape drive and TS1120 tape drive can sense and
report the scaling state of current medium by using the SCSI Mode Sense command
and specifying Mode Page X'23'. Capacity scaling is only offered on the JA and JB
media types.
