Re: [PATCHES] Bitmapscan changes

<p><font size="2">Wow, nice!<br /><br /> Can you tell us:<br /> - how big is the table<br /> - cardinality of the
column<br/> - how big is the index in each case<br /> - how much memory on the machine<br /> - query and explain
analyze<br/><br /> Thanks!<br /><br /> - Luke<br /><br /> Msg is shrt cuz m on ma treo<br /><br />  -----Original
Message-----<br/> From:   Grzegorz Jaskiewicz [<a href="mailto:gj@pointblue.com.pl">mailto:gj@pointblue.com.pl</a>]<br
/>Sent:   Saturday, March 17, 2007 05:16 PM Eastern Standard Time<br /> To:     Joshua D.Drake<br /> Cc:     Heikki
Linnakangas;PostgreSQL-development Hackers<br /> Subject:        Re: [HACKERS] [PATCHES] Bitmapscan changes<br /><br />
Thisis on dual ultra 2 sparc. with ultrawide 320 scsi drives. 512MB <br /> ram.<br /> I had to drop size of DB, because
theDB drive is 4GB (I do welecome <br /> bigger drives as donation, if someone asks - UWscsi 320).<br /><br /> here are
myresults. With only 4.2 patch (no maintain cluster order <br /> v5 patch). If the v5 patch was needed, please tell me
-I am going <br /> rerun it with.<br /><br /> hope it is usefull.<br /><br /> Repeat 3 times to ensure repeatable
results.<br/> Timing is on.<br /> select_with_normal_index<br /> --------------------------<br />                    
100000<br/> (1 row)<br /><br /> Time: 1727891.334 ms<br /> select_with_normal_index<br /> --------------------------<br
/>                    100000<br /> (1 row)<br /><br /> Time: 1325561.252 ms<br /> select_with_normal_index<br />
--------------------------<br/>                     100000<br /> (1 row)<br /><br /> Time: 1348530.100 ms<br /> Timing
isoff.<br /> And now run the same tests with clustered index<br /> Timing is on.<br /> select_with_clustered_index<br
/>-----------------------------<br />                        100000<br /> (1 row)<br /><br /> Time: 870246.856 ms<br />
select_with_clustered_index<br/> -----------------------------<br />                        100000<br /> (1 row)<br
/><br/> Time: 477089.456 ms<br /> select_with_clustered_index<br /> -----------------------------<br />
                      100000<br /> (1 row)<br /><br /> Time: 381880.965 ms<br /> Timing is off.<br /><br /><br /><br
/><br/> ---------------------------(end of broadcast)---------------------------<br /> TIP 9: In versions below 8.0,
theplanner will ignore your desire to<br />        choose an index scan if your joining column's datatypes do not<br />
      match<br /><br /></font>