Re: PSPP goals

[Ben Pfaff]

John Darrington <address@hidden> writes:

> On Tue, Aug 02, 2005 at 07:10:15PM -0700, Ben Pfaff wrote:
>      John Darrington <address@hidden> writes:
>      
>      > Some time ago I did an experiment on PSPP sorting  a data file with 
>      > ~8 million records.  It took about 20mins to do, but performed without 
> a hitch.
>      
>      How big was each record?  
>
> 11 variables.

Let's set, that's about (8*11*8,000,000) / (1024*1024) = 671 MB.

>      What was the PSPP workspace size?
>
> Whatever the default is.

4 MB then.  So it probably had to do about 671*4 MB or roughly
2.5 GB of disk activity.  Not an unreasonable amount of time,
then, but it would probably be much faster with a bigger
workspace size.

Perhaps we should try to size the workspace based on the
machine's RAM size.
-- 
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