IBM TS4500, Introduction And Planning Manual

Page: 40 / 218

Table 9. Features of the 3592 tape drive (continued)
Feature TS1155 tape drive TS1150 tape drive TS1140 tape drive
Host (server) attachment Supports dual-port, 8
Gbps Fibre Channel
interface
Supports dual-port, 8
Gbps Fibre Channel
interface
Supports dual-port, 8 Gbps Fibre
Channel interface
Maximum interface burst
transfer rate of 800 MB/s
Maximum interface burst
transfer rate of 800 MB/s
Maximum interface burst transfer
rate of 800 MB/s
Supports N and L ports
with auto-configure
Supports N and L ports
with auto-configure
Supports N and L ports with
auto-configure
Encryption All TS1155 tape drives
are encryption capable
All TS1150 tape drives
are encryption capable
All TS1140 tape drives are
encryption capable
Notes:
1. The compression ratio for the 3592 tape cartridges is 3:1.
2. The 55F format is the native format for both the 3592 Model 55F, and 3592 Model 55E.
The 3592 tape drives provide the following performance, capacity, and availability
features:
N+1 power supplies
When installed in a TS4500 tape library frame, these power supplies
increase drive availability in the event of a power failure.
Media reuse
The 3592 tape drives can reuse different types of tape and multiple
densities (logical formats) across various drive generations. These logical
formats can be divided into multiple sub-format options, such as
segmentation and capacity scaling. For a matrix of read and write
compatibility by cartridge and format type, refer to “Mixed media in
drives” on page 32.
Speed matching
When the drives operate in a host environment where the net host data
rate is less than the maximum drive native data rate, 3592 tape drives
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 is
factored out). A reduction in back-hitches improves system performance.
High resolution tape directory (HRTD)
The HRTD directory structure, which is in 3592 tape drives, allows fast and
consistent nominal and average access times for locate operations.
Channel calibration and dynamic 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 TS1140,
TS1150, and TS1155 tape drives also use dynamic adaptive equalization
hardware on an ongoing basis to adjust the read equalization response.
Recursive accumulating backhitchless flush
TS1140, TS1150, and TS1155 tape drives use an algorithm called recursive
accumulating backhitchless flush (or non-volatile caching). This algorithm
22
IBM TS4500: Introduction and Planning Guide