Re: OT: Somewhat.... KSAM equivilent on the 9000
> I'm still straddling between the 3000 and 9000 worlds, and I am still
> not fully embracing UNIX because I'm convinced it is a cruel joke.
> I am loving Eloquence on the 9000 because it gives me that warm fuzzy
> feeling of home with Image on the 3000, but I am trying to figure out
> what is the equivalent of a KSAM file on UNIX?
> Are KSAM files truly not needed?
> I'm trying to setup a quick cross reference file for simple data (five
> data items), but 10s of thousands of records. Sure I can setup a flat
> file, but serial reads of that seem like it would be costly.[/color]
We asked ourselves the same question several years ago when we first began
migrating QueryCalc to the 9000. We made heavy use of KSAM files on the
HP3000, and for a while I thought our goose might be cooked without KSAM.
But then I began to analyze the KSAM files that we and our customers were
generating. A file 15,000 records in length was a real outlier. Most of the files
were only a few hundred to a couple of thousand records in length, so I began
test serial reads on files that size in UNIX. Let me say that I was pleased to
find that data extraction was at least as fast (if not significantly faster) than
doing indexed KSAM retrievals on the HP3000.
For files of a very small number of records, a b-tree-, KSAM-like index actually
slows you down. Where the index pays for itself in spades is when it's applied
to files containing millions of records. But for intermediate file sizes,it's a bit of
Ultimately, we just went with serial reads. We were still able to get subsecond
response times, and in the end, that's all that matters.
* To join/leave the list, search archives, change list settings, *
* etc., please visit [url]http://raven.utc.edu/archives/hp3000-l.html[/url] *