* Robert Haas (robertmh...@gmail.com) wrote: > On the PPC64 machine I normally use for performance testing, it takes > about 6.3 seconds to build the index with the commit just before this > one. With this commit, it drops to 1.9 seconds. That's more than a > 3x speedup! > > Now, if I change the query that creates the table to this. > > rhaas=# create table stuff as select 'aaaaaaaa' || random()::text as > a, 'filler filler filler'::text as b, g as c from generate_series(1, > 1000000) g; > > ...then it takes 10.8 seconds with or without this patch. In general, > any case where the first few characters of every string are exactly > identical (or only quite rarely different) will not benefit, but many > practical cases will benefit significantly. Also, Peter's gone to a > fair amount of work to make sure that even when the patch does not > help, it doesn't hurt, either. > > So that's pretty cool.
Wow, nice!
Good work Peter!
Thanks,
Stephen
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