June 1999
Graduate to more performance
A commencement address to those
ready to move on to faster HP 3000 systems
By Mike Hornsby
Speed costs money. How fast do
you want to go? You want to get all of the speed out of your current HP
3000 configuration. There are ways of trimming existing costs and applying
the savings to improved performance. This article provides insights and
methodologies for saving on ongoing costs and improving interactive
response times and batch throughput.
Speed traps
If youre using DTCs, are the
terminals running at 19.2 kbaud? Do you have more than four disks per HP-IB
or single ended SCSI interface? Do you have a single LANIC for all network
traffic? Have you switched to Jetdirect or LPD-based printing sharing?
Hardware options
Maximize your memory
configuration/interleave. Switch to Web or socket interfaces to reduce
hpusercount, allowing a faster server with a smaller
hpuserlimit. Add disc drives in user volumes to spread
transaction management. Add or upgrade tape devices to speed up backup
operations. Split your fourth-generation language and reporting licenses
into developers and runtime licenses, and put the developers on a separate,
limited-user system.
Database management
Make sure that datasets are blocked
efficiently to save disk space and maximize serial prefetching. If
youre performing chained reads, repack on a periodic basis. Place
your heaviest accessed files on Fast/Wide SCSI disks. Use HWMPUT or a
serial repack to avoid a deleted entry chain. Split your automatic master
for small detail from those associated with large details. Watch for master
capacities that cause clustering. Avoid the use of master dynamic expansion
except for emergency overflows.
Process management
Tune your CQ=152,200,200,2000 if
youre using VPlus. Otherwise, tune CQ=152,200,100,2000. Watch for
socket applications such as ODBC always running at 152. Use NSCONTROL
SERVER=MIN,MAX to pre allocate server processes.
Logging
If youre using mirroring or
RAID 5, reevaluate the requirement for logging. If you are logging, make
sure that proper procedures are followed after system aborts.
OCTCOMP/Allocate
Object Code Translate and allocate
Compatibility Mode programs such as FCOPY and any other user CM programs.
Install the Native Mode versions of QUERY and QUAD if you use them.
Lot-o-spoolfiles
If youre using spooling
utilities, minimize the number of spoolfiles on the system. Use set
stdlist=delete in trivial batch jobs. If a program produces a large
stdlist, send it to a circular file. At reboot, the system must recover any
spoolfiles that were opened at the time of a crash. This used to be done
prior to SYSSTART, but now is a background process but it still can
hog the system for a while. Also, doing a print ;start=-20 on a large
spoolfile causes all records to be read, because spoolfiles have variable
records.
Backups
The backup is usually the single
longest, most intensive job. Many times, slow response during the day can
be attributed to an online restore. Use the store listing or BIGFILES to
identify the largest files. It is a shame to waste time backing up memory
dumps or month-end work files in each full back up. It is a crime to wait
for these files to roll in during a re-install!
Free tools
Some tools that are available for
free: At www.beechglen.com:
BIGFILES, a utility to list the files on the system in descending order by
size w/cutoff. QPLUS, a command file script that approximates GLANCE or
SOS.
At www.allegro.com, or via the Lund Performance Systems tools tape:
FILERPT, a utility that summarizes file usage from system log files.
SYSLOG, a utility that allows dynamic switching of system log file events.
RAMUSAGE, a utility that describes memory content better than GLANCE.
DBLOADNG, a utility to report on database efficiencies
Application tips
Dont use PIC 9 fields in
COBOL for arithmetic operations. The overhead for ASCII-to-binary is
substantial. Do use VPlus forms caching. This is easy to implement in the
COM area, and most terminals and emulators support it.
Use DBUPDATE in place of
delete/put; this CIUPDATE feature can dramatically reduce the overhead to
modify a search or sort item. Do use mode 6 DBGET w/date cut off. Many
programs read down the chain selecting for date >, until end of chain.
It is usually much faster to read up the chain stopping at date <.
IMAGE does not prefetch for either
mode 5 or 6 DBGETS.
Do use Robelles Suprtool to
extract/sort work files. Many systems have one or two killer
batch reports. These usually sequentially read a master and chain to a
detail producing a work file that is then sorted and passed to a report or
output section. Suprtool can usually produce the same work file in
one-tenth of the time.
Do use IMAGE b-trees to replace
KSAM look up files. IMAGE now has the capability to incorporate b-tree
lookups. It is very easy to implement and very transparent to the
application code.
Other cost-saving options
Have leased-line and ISP agreements
re-quoted annually. Just by asking you can usually save 10-15 percent.
Review hardware and software maintenance agreements annually. Look for
items that you already have spares for terminals, DTCs, and tape
drives, or thosethat can be replaced inexpensively.
Eliminate OpenView. Many sites have
this product to allow DTC switching. This was bundled into MPE/iX 5.5 as
host-based DTC control, along with host based Telnet. Look to grow
operations and user staff into programmers. Which would you rather have: a
great programmer that doesnt know the business, or a fair programmer
that already knows the business and people well?
Mike Hornsbys company
Beechglen Consulting (513.922.0509) provides contract administration,
contract programming, and customized system and application software
support, specializing in HP 3000s and promoting an Anyone can call
about anything philosophy. A former HP senior systems engineer, he
co-founded Beechglen in 1988.
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