I can appreciate what you are doing as an academic exercise.

You seem happy how it looks at this moment, where, because you set "MINIMUM.MODULUS 118681", you ended up with a current load of 63%. But think about it: as you add records, the load will reach 70%, per "SPLIT.LOAD 70", then splits will keep occuring and current modlus with grow past 118681. MINIMUM.MODULUS will never matter again. (This was described as an ever-growing file.)

If the current config is what you want, why not just set "SPLIT.LOAD 63 MINIMUM.MODULUS 1". That way the ratio that you like today will stay like this forever.

MINIMUM.MODULUS will not matter unless data is deleted. It says to not shrink the file structure below that minimally allocated disk space, even if there is no data to occupy it. That's really all MINIMUM.MODULUS is for.

Play with it all you want, because it puts you in a good place when some crisis happens. At the end of the day, with this file, you'll find your tuning won't matter much. Not a lot of help, but not much harm if you tweak it wrong, either.

On 7/5/2012 1:20 PM, Chris Austin wrote:

You are correct, I should be using the smaller size (I just haven't changed it 
yet). Based on the reading I have done you should
only use the larger group size when the average record size is greater than 
1000 bytes.

As far as being better off with the defaults that's basically what I'm trying 
to test (as well as learn how linear hashing works). I was able
to reduce my overflow by 18% and I only increased my empty groups by a very 
small amount as well as only increased my file size
by 8%. This in theory should be better for reads/writes than what I had before.

To test the performance I need to write a ton of records and then capture the 
output and compare the output using timestamps.


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