Re: vacuum timings

> Bruce Momjian <pgman@candle.pha.pa.us> writes:
> > I loaded 10,000,000 rows into CREATE TABLE test (x INTEGER);  Table is
> > 400MB and index is 160MB.
> 
> > With index on the single in4 column, I got:
> >      78 seconds for a vacuum
> >     121 seconds for vacuum after deleting a single row
> >     662 seconds for vacuum after deleting the entire table
> 
> > With no index, I got:
> >      43 seconds for a vacuum
> >      43 seconds for vacuum after deleting a single row
> >      43 seconds for vacuum after deleting the entire table
> 
> > I find this quite interesting.
> 
> How long does it take to create the index on your setup --- ie,
> if vacuum did a drop/create index, would it be competitive?

OK, new timings with -F enabled:
index    no index519    same    load    247    "    first vacuum40    "    other vacuums1222    X    index creation90
X    first vacuum80    X    other vacuums<1    90    delete one row121    38    vacuum after delete 1 row346    344
deleteall rows440    44    first vacuum20    <1    other vacuums(index is still same size)
 

Conclusions:
o  indexes never get smallero  drop/recreate index is slower than vacuum of indexes

What other conclusions can be made?

--  Bruce Momjian                        |  http://www.op.net/~candle pgman@candle.pha.pa.us               |  (610)
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