HP 3000 Manuals HP 3000 Manuals
Introducing TurboSTORE XL
by Lynn Parker
Commercial Systems Division
TurboSTORE XL (HP 30319A) is available with this release of MPE XL. This
new product includes all the functionality of STORE/RESTORE as well as
important performance enhancements. These performance enhancements will
significantly reduce system backup scheduled downtime. This is possible
due to a technique available with TurboSTORE XL called file interleaving.
With file interleaving, TurboSTORE XL can access multiple disc files
allowing it a much higher disc to tape I/O transfer rate than
STORE/RESTORE. In addition, backup time can be reduced even further
because TurboSTORE XL can store to multiple tape drives in parallel.
Taking advantage of these options can reduce system backup time to almost
1/3 of that required by STORE/RESTORE.
The following describes the TurboSTORE XL syntax as well as the new
MAXTAPEBUF, INTER, STORESET and RESTORESET options.
TURBOSTORE STORE COMMAND SYNTAX
TurboSTORE XL syntax is completely compatible with the version of STORE
XL included with this release of MPE XL. Any command line that is valid
for STORE XL will work exactly the same with TurboSTORE XL. File
interleaving and multiple backup devices, which are additional
performance features, are implemented as new command line options.
Syntax
:STORE [ filesetlist ] [ ;[ storefile ] [ ;option [ ;...] ] ]
where option is
;SHOW [ = showparmlist ]
;ONERROR = recoverytype
;FILES = maxfiles
;DATE <= accdate
>= moddate
;PURGE
;PROGRESS [ = #minutes ]
;FCRANGE = filecocde/filecode [ ,filecode/filecode [ ,...] ]
;DIRECTORY
;TRANSPORT
;ONVS = volumesetname [ ,volumesetname ]
;MAXTAPEBUF (*NEW*)
*** SPECIAL TURBOSTORE FEATURES ***
;INTER
;STORESET = ( device [ ,...] ) [ ,( device [ ,...] ) , [ ,...] ]
Refer to the TurboSTORE XL Reference Manual (P/N 30319-60002) for a
complete discussion of the options.
The MAXTAPEBUF Option
MAXTAPEBUF is a new STORE XL option available with this release of MPE
XL, which is also available with the TurboSTORE XL product. Specifying
this option on the command line results in TurboSTORE determining the
optimal record size to use with the specified backup device. This
optimal record size is equal to the largest possible record size that
TurboSTORE can use for writing to the backup media. Using MAXTAPEBUF
improves backup performance due to more efficiently sending data to the
backup device (via larger size transfers), as well as reducing the amount
of media consumed by inter record gaps.
TurboSTORE will automatically determine the best record size to use with
each type of backup device since this size varies according to the device
specified. Listed below are the maximum record sizes corresponding to
each device type supported by TurboSTORE XL:
Tape Drive Model Maximum Record Size
7974 16 KB
7976 16 KB
7978A 16 KB
7978B 16 KB
7979 32 KB
7980 32 KB
The INTER Option
Inclusion of the INTER option on the TurboSTORE command line results in a
request for TurboSTORE to read from multiple files that reside on
different discs simultaneously. TurboSTORE then blocks these records
together and sends them to the backup device in a single operation. This
results in a much higher disc data rate, thus matching the slow speed of
the input devices (disc drives) to the fast output device (a streaming
tape drive).
The fact that TurboSTORE XL processes multiple files concurrently is
virtually transparent. TurboSTORE writes data to the backup media in the
same format as STORE XL. So tapes generated by TurboSTORE XL are fully
compatible with STORE XL tapes of versions 2.0 or greater. The only
difference that may be noticed is that files may not be stored in the
sequence specified in the fileset list (since TurboSTORE stores those
files residing on different devices rather than one at a time).
TurboSTORE will display the file names in order on the file listing but
there may not be a smooth transition from one reel number to the next.
The STORESET Option
The STORESET option specifies that TurboSTORE XL store files to multiple
backup devices. There are three ways to utilize this feature.
1. Consecutive Backup Devices
Consecutive backup devices are those listed and enclosed in parenthesis
after the STORESET option. For example:
;STORESET = ( *tape1 , *tape2 , *tape3 )
results in TurboSTORE first selecting the device referenced as *tape1,
storing to this device, then as tape1 rewinds and is reloaded TurboSTORE
selects tape2, then on to tape3, back to tape 1 and so on. Only one
device is the target of TurboSTORE at any given time. The performance
gain here is that TurboSTORE can be writing to the next device while the
first is rewound and its reel changed.
2. Concurrent Backup Devices
Concurrent backup devices are those specified as a list of devices each
enclosed in parenthesis. For example:
;STORESET = ( *tape1 ) , ( *tape2 ) , ( *tape3 )
requests that the three devices referenced by the tape equations be
stored to in parallel; TurboSTORE will store files to all three devices
at the same time.
3. Parallel Device Pools
Parallel device pools are a combination of the two; pools of concurrent
devices are specified to be stored to concurrently. For example:
;STORESET = ( *tape1 , *tape2 ) , (*tape3 , *tape4 )
results in TurboSTORE writing to two devices at any given time. Those
devices referenced by tape1 and tape3 ( the first device in each set) are
stored to in parallel at first. As these devices rewind and are
reloaded, TurboSTORE will send data to the second devices in each set (
tape2 and tape4). Using parallel device pools gives both the benefit of
continued storing during reel rewinds and tape mounts as well as the
great performance boost of writing to multiple devices in parallel.
TURBOSTORE RESTORE COMMAND SYNTAX
The syntax for the TurboSTORE XL :RESTORE command and a description of
the RESTORESET option follows.
Syntax
:RESTORE [ restorefile ] [ ; [ filesetlist ] [ ; option [ ;...] ] ]
where option is
;DEV = device
;SHOW [ = showparmlist ]
;FILES = maxfiles
{ LOCAL }
; { GROUP = groupname } [ ,...]
{ ACCOUNT = accountname }
{ GROUP }
;CREATE [ = { ACCT } [ ,...]]
{ CREATOR }
;CREATOR [ = username ]
{ KEEP }
;{ NOKEEP }
{ OLDDATE }
;{ NEWDATE }
{ SKIP }
;ONERROR = { QUIT }
;DIRECTORY
;LISTDIR
;FCRANGE = filecode/filecode [ ,...]
;VOLSET = volumesetname
;VOL = volumename
;VOLCLASS = volumeclassname
*** SPECIAL TURBOSTORE FEATURE ***
;RESTORESET = ( device [ , device [ ,...] ] )
Refer to the TurboSTORE XL Reference Manual (P/N 30319-60002) for a
complete description of the options.
The RESTORESET Option
The RESTORESET option can be used on the RESTORE command line to specify
consecutive backup devices. For example:
;RESTORESET = ( *tape1 , *tape2 )
requests that TurboSTORE restore from the tapeset reels on the backup
devices referenced as tape1 and tape2. TurboSTORE will be busy restoring
files from one device at a time; this allows the restore to continue on
one drive while another is rewinding and while mounting new reels.
HARDWARE/CONFIGURATION RECOMMENDATIONS
TurboSTORE XL is executable on any configuration supported by MPE XL, but
in order to take advantage of the faster backup features the following
hardware configurations are recommended:
Basic Requirements:
* A configuration including at least two tape drives to be used as
backup devices. These can be any combination of 7978, 7979, 7980,
and/or 7980xc models.
* If the devices will be stored to in parallel or used in parallel
device pools, it is suggested that each tape drive be connected to
its own HP-IB device adapter.
* If the backup devices will be stored to sequentially only, then they
may share an HP-IB device adapter.
Requirements for Optimum Performance Gain:
* Three or more tape drives included in the configuration. These
should be 7980 and/or 7980xc models.
* Eagle disks connected to at least one A-link device adapter are
preferred. If HP-IB disks are used, then they should be spread over
at least four HP-IBs.
* The following suggestions will further speed up the transfer rate
during a TurboSTORE:
* Have a maximum of two A-link devices adapters per channel.
* Do not have an HP-IB and A-link device adapter on the same
channel.
* Have at most three HP-IB device adapters per channel.