Chuck,
 
We do exactly that in Jbase (also did it in UV). It is especially useful in  
EOD/EOM processing. We have our product files distributed by our 25 stores.  
We've found that you need to limit the select phantoms to a smaller number of  
concurrent processes. With our present configuration (4 CPUs), 5 is about 
right.  The code is embedded in the main programs, but could easily be split 
out 
into  free-standing utilities. We use the lists separately since access to a 
part file  is faster than accessing the whole distributed file. We also have a 
merge-lists  utility that could be used.
 
All that being said, I'd be very cautious in using this method during the  
day - the users know where to find you, and they carry big sticks!   ;^)
 
Regards,
Charlie Noah
 
[EMAIL PROTECTED] (mailto:[EMAIL PROTECTED])   
writes:

Has  anyone written a utility to split out selects for distributed files,
1  phantom for each partfile, then pin the results into 1 select or  saved
list?
The purpose would be to decrease total elapsed time for a  given select
on the big type30 file.
Was it worth it?

In  pseudo-code, something like:

get  Selection-Criteria
for partno = 1 to number of  part-files
phantom: SELECT partfile_partno  [Selection-Criteria];
savelist [tempname]-[partno]
next  partno
wait for all phantoms to finish
merge  all savedlists into active select list

You get the idea.

It  could be implemented as verbs, SELDISTRIB & SSELDISTRIB.  Or  even
just intercept SELECT and SSELECT, but simply executing the real  thing
if it finds the file is not distributed.

Of course, the same  amount of data needs to be traversed and digested,
so this actually  (slightly) increases total consumption of system
resources due to the  additional overhead.  Possible i/o & even  cpu
contention.

What was your experience?


Thank-you for  the sage advice,
Chuck Stevenson
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