RE: Some new results

[rob@xxxxxxxxx]

Thanks for all the testing.  And hopefully we'll be able to contribute.

I think one of the points of the old discussion is the flexibility.  For
example, if I had a utility program that maintained multiple versions of a
package, like bpcs 405cd and 8.xx, and it was used in an interactive
screen, then you'd be hard pressed to find a data entry clerk who noticed
the difference between an INSERT and a WRITE.  But with the INSERT, you
could have one program supporting both versions.

Rob Berendt
--
Group Dekko Services, LLC
Dept 01.073
PO Box 2000
Dock 108
6928N 400E
Kendallville, IN 46755
http://www.dekko.com


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|   "Joe Pluta"               |                                           |
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|      RPG programming on the |                                   <rpg400-|
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> From: Joe Pluta
>
> I was not surprised to find that, as usual, WRITE is ten times faster
> than INSERT VALUES.  However, I WAS very interested to find that
INSERT
> VALUES was actually a tiny bit FASTER than INSERT data structure.  And
> while INSERT MODS of ten rows was a smidge faster than INSERT VALUES
> (less than 1% faster), INSERT MODS with 100 rows was actually SLOWER
> than INSERT MODS with ten rows.  And finally, all four techniques were
> within 1% of each other, and all were ten times as slow as native I/O.

I HATE when that happens...

I should have been suspicious of the results.  I knew it.  While the
numbers on the INSERT VALUES and INSERT DS are correct, the INSERT MODS
was bogus.  I was running the wrong program.

The test results are MUCH more realistic now:

1. INSERT 10 rows at a time is three times slower than WRITE
2. INSERT 100 rows at a time is 25% faster than WRITE

So it looks like the break-even point, at least for SQL INSERT vs.
blocked WRITE, is somewhere around 80 rows or so at a time.  But even at
more modest 10 rows at a time, it's not a horrible amount of overhead.

But record at a time INSERTs, no matter how you slice them, are awful.

Joe

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