HP 3000 Manuals HP 3000 Manuals
Improving Storing Efficiency by Increasing Record Size
Files are stored with the greatest efficiency by using the maximum tape
record (buffer) size allocated to a given backup device. Performance
increases because data transmission is more efficient and because the
amount of media used for interrecord gaps decreases.
The maximum tape record size of MPE/iX supported backup devices differs
from device to device and is shown in Table 6-2 below:
Table 6-3. Maximum Tape Record Sizes
-----------------------------
| |
| Tape Drive Record Size |
| |
-----------------------------
| |
| HP 7974 16 Kbytes |
| |
| HP 7978A 16 Kbytes |
| |
| HP 7978B 32 Kbytes |
| |
| HP 7979 32 Kbytes |
| |
| HP 32 Kbytes |
| 7980(XC,S,SX) |
| |
| DDS(all) 32 Kbytes |
| |
| 3480 32KB |
| |
| MO 32KB |
| |
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STORE uses a default record size of 16 kilobytes. To use the maximum
record size of the device instead, specify the MAXTAPEBUF parameter of
the STORE command.
NOTE Do not use the MAXTAPEBUF parameter with a backup device of
32-kilobyte record size if you anticipate restoring the tape to a
backup device whose maximum record size is 16 kilobytes.