Re: Odd/Even packed numbers.

[Vern Hamberg <vhamberg@xxxxxxxxxxxxxxxxxxxxxxxxx>]

Giuseppe, I've not tested this, in recent memory, at least. But you could
do a simple test.

Declare 2 variables, the first 8,0 and the second 9,0.
Retrieve the time and DSPLY it.
Do a loop with 100,000 iterations (or 1,000,000) that keeps adding 1 to the
first variable.
Retrieve the time and DSPLY it.
Do another loop with 100,000 iterations (or 1,000,000) that keeps adding 1
to the second variable.
Retrieve the time and DSPLY it.
Compare the times.

Modifications could include a multiple instance of each type;
multiplication; etc.

Then you have some base point for your consideration. If you have enough
calculations involving one of these, you can decide.

I assume there is still extra work to put the 0-nibble at the beginning of
the byte-string.

HTH

Vern

At 11:20 AM 11/28/02 +0100, you wrote:
> In the past (at S/38 times) we have been told that odd packed numbers were
> not so efficient as even ones, and that - at design time - it was better to
> define even packed numbers (for example 9.0 instead of 8.0).
>
> The simple anwser could be to use 9.0 because it occupies the same storage
> as 8.0, but unfotunately it occupies also one more byte in reports, panels,
> etc. and - with other values - another byte for one more decimal separator.
>
> Is there any evidence that with RISC processors this is still true?
> If so, how much system performances could degrade in case of large files?
>
> -- Giuseppe