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<P><FONT SIZE=2>Okay you can dance. I'll say its a tie so all can dance :)<BR>
<BR>
-----Original Message-----<BR>
From: postgis-devel-bounces@postgis.refractions.net on behalf of Paul Ramsey<BR>
Sent: Wed 1/21/2009 3:17 PM<BR>
To: PostGIS Development Discussion<BR>
Subject: Re: [postgis-devel] Another Data Point<BR>
<BR>
15 seconds on OpenJump. I'll take my victories where I can get them,<BR>
this is close enough.<BR>
<BR>
P<BR>
<BR>
On Wed, Jan 21, 2009 at 11:53 AM, Obe, Regina <robe.dnd@cityofboston.gov> wrote:<BR>
> I don't have my OpenJump available at the moment.<BR>
><BR>
> Kevin or Paul you happen to have that? If not then I guess I can test<BR>
> tomorrow and<BR>
> then Paul can do his little dance :)<BR>
><BR>
> Though would make more sense for Paul to do it so we are testing on the same<BR>
> hardware.<BR>
><BR>
><BR>
> -----Original Message-----<BR>
> From: postgis-devel-bounces@postgis.refractions.net on behalf of Paul Ramsey<BR>
> Sent: Wed 1/21/2009 2:50 PM<BR>
> To: PostGIS Development Discussion<BR>
> Subject: Re: [postgis-devel] Another Data Point<BR>
><BR>
> Now can I do my little dance?<BR>
><BR>
> uniontest=# SELECT geometrytype(_unite_garray_fast(ARRAY(SELECT<BR>
> the_geom FROM sample_poly)));<BR>
> geometrytype<BR>
> --------------<BR>
> MULTIPOLYGON<BR>
> (1 row)<BR>
><BR>
> Time: 24122.901 ms<BR>
> uniontest=#<BR>
><BR>
><BR>
><BR>
> On Wed, Jan 21, 2009 at 11:43 AM, Obe, Regina <robe.dnd@cityofboston.gov><BR>
> wrote:<BR>
>> Paul,<BR>
>> I wouldn't proclaim victory on that alone.<BR>
>><BR>
>> Do another test. 20 seconds sounds a little too short.<BR>
>> I'm not saying it isn't right and my memory may be wrong on the JTS result<BR>
>> too.<BR>
>> Besides JTS would have to collect geometries as well I imagine so you<BR>
>> can't<BR>
>> simply throw that out and proclaim victory.<BR>
>><BR>
>><BR>
>> Test out<BR>
>><BR>
>> SELECT geometrytype(st_unite_garray(ARRAY(SELECT the_geom FROM<BR>
>> sample_poly)))<BR>
>><BR>
>> Though that wouldn't be quite a true test either. But somewhere between<BR>
>> the<BR>
>> two would be the answer.<BR>
>><BR>
>><BR>
>> -----Original Message-----<BR>
>> From: postgis-devel-bounces@postgis.refractions.net on behalf of Paul<BR>
>> Ramsey<BR>
>> Sent: Wed 1/21/2009 1:58 PM<BR>
>> To: PostGIS Development Discussion<BR>
>> Subject: Re: [postgis-devel] Another Data Point<BR>
>><BR>
>> Well, just running this:<BR>
>><BR>
>> uniontest=# select geometrytype(collect(the_geom)) from sample_poly;<BR>
>> geometrytype<BR>
>> --------------------<BR>
>> GEOMETRYCOLLECTION<BR>
>> (1 row)<BR>
>><BR>
>> Time: 261624.195 ms<BR>
>><BR>
>> takes 251 of the 271 seconds the union operation took... the<BR>
>> implication is that the GEOS portion of the work is on the order of 10<BR>
>> seconds.<BR>
>><BR>
>> P.<BR>
>><BR>
>> On Wed, Jan 21, 2009 at 10:10 AM, Martin Davis <mbdavis@refractions.net><BR>
>> wrote:<BR>
>>> Could be... It would be interesting to see whether GEOS is faster than<BR>
>>> JTS. Needs a test environment able to run both pieces of code on the<BR>
>>> same<BR>
>>> hardware.<BR>
>>><BR>
>>> Paul Ramsey wrote:<BR>
>>>><BR>
>>>> I got another run in, right near the end, and it showed that<BR>
>>>> GEOSUnionCascaded took only about 50% of the time in that slice. There<BR>
>>>> was still more memcpy'ing first. I bet GEOSUnionCascaded on its own<BR>
>>>> would be as fast as JTS (or faster?).<BR>
>>>><BR>
>>>> P.<BR>
>>>><BR>
>>>> On Wed, Jan 21, 2009 at 9:05 AM, Paul Ramsey <pramsey@cleverelephant.ca><BR>
>>>> wrote:<BR>
>>>><BR>
>>>>><BR>
>>>>> Interesting! The Shark only samples for about 20 seconds, so I only<BR>
>>>>> got the first 10% or so of the run, and the biggest user in that time<BR>
>>>>> period memcpy'ing in LWGEOM_accum (postgis) and<BR>
>>>>> advance_transition_function (pgsql). So we are spending a non-trivial<BR>
>>>>> amount of time just accumulating the input...<BR>
>>>>><BR>
>>>>> P<BR>
>>>>><BR>
>>>>> On Wed, Jan 21, 2009 at 9:00 AM, Paul Ramsey<BR>
>>>>> <pramsey@cleverelephant.ca><BR>
>>>>> wrote:<BR>
>>>>><BR>
>>>>>><BR>
>>>>>> The glove is dropped indeed... why speculate when I have the Shark...<BR>
>>>>>> time to see where our time goes...<BR>
>>>>>><BR>
>>>>>> P<BR>
>>>>>><BR>
>>>>>> On Wed, Jan 21, 2009 at 8:55 AM, Martin Davis<BR>
>>>>>> <mbdavis@refractions.net><BR>
>>>>>> wrote:<BR>
>>>>>><BR>
>>>>>>><BR>
>>>>>>> Go for it, Regina! The glove is dropped...<BR>
>>>>>>><BR>
>>>>>>> Although I suspect this test may simply be running into the slower<BR>
>>>>>>> memory<BR>
>>>>>>> performance due to any or all of Postgres, C, GEOS compared to good<BR>
>>>>>>> ol'<BR>
>>>>>>> Java... Hard to beat that tuned JVM memory manager!<BR>
>>>>>>><BR>
>>>>>>> Obe, Regina wrote:<BR>
>>>>>>><BR>
>>>>>>>><BR>
>>>>>>>> Ah I think JTS was able to do this in about 40-50 seconds. And my<BR>
>>>>>>>> version was able to beat out Kevin's nested by a small margin. I'll<BR>
>>>>>>>> retest on mine.<BR>
>>>>>>>><BR>
>>>>>>>> So I think we still need work here.<BR>
>>>>>>>><BR>
>>>>>>>> I'm curious what would happen if I combined the algorithm I wrote<BR>
>>>>>>>> with<BR>
>>>>>>>> the new ST_Union how things would fair. In theory it should fair<BR>
>>>>>>>> the<BR>
>>>>>>>> same, but I'm not really using Martin's cascaded union algorithm to<BR>
>>>>>>>> the<BR>
>>>>>>>> letter.<BR>
>>>>>>>><BR>
>>>>>>>><BR>
>>>>>>>> -----Original Message-----<BR>
>>>>>>>> From: postgis-devel-bounces@postgis.refractions.net<BR>
>>>>>>>> [<A HREF="mailto:postgis-devel-bounces@postgis.refractions.net">mailto:postgis-devel-bounces@postgis.refractions.net</A>] On Behalf Of<BR>
>>>>>>>> Paul<BR>
>>>>>>>> Ramsey<BR>
>>>>>>>> Sent: Wednesday, January 21, 2009 12:50 AM<BR>
>>>>>>>> To: PostGIS Development Discussion<BR>
>>>>>>>> Cc: lee.keel@uai.com<BR>
>>>>>>>> Subject: [postgis-devel] Another Data Point<BR>
>>>>>>>><BR>
>>>>>>>> Using the original sample set from Lee Keel,<BR>
>>>>>>>><BR>
>>>>>>>> With the old style ST_Union, 3 hours, 27 minutes:<BR>
>>>>>>>><BR>
>>>>>>>> uniontest=# select st_area(st_union(the_geom)) from sample_poly;<BR>
>>>>>>>> st_area<BR>
>>>>>>>> --------------------<BR>
>>>>>>>> 0.0324039850011104<BR>
>>>>>>>> (1 row)<BR>
>>>>>>>><BR>
>>>>>>>> Time: 12419261.819 ms<BR>
>>>>>>>><BR>
>>>>>>>><BR>
>>>>>>>> With the new cascaded ST_Union, 4 minutes, 30 seconds, or 46 times<BR>
>>>>>>>> faster.<BR>
>>>>>>>><BR>
>>>>>>>> uniontest=# select st_area(st_union_fast(the_geom)) from<BR>
>>>>>>>> sample_poly;<BR>
>>>>>>>> st_area<BR>
>>>>>>>> --------------------<BR>
>>>>>>>> 0.0324039850054305<BR>
>>>>>>>> (1 row)<BR>
>>>>>>>><BR>
>>>>>>>> Time: 271618.181 ms<BR>
>>>>>>>><BR>
>>>>>>>><BR>
>>>>>>>> That's one nasty data set.<BR>
>>>>>>>><BR>
>>>>>>>> P.<BR>
>>>>>>>> _______________________________________________<BR>
>>>>>>>> postgis-devel mailing list<BR>
>>>>>>>> postgis-devel@postgis.refractions.net<BR>
>>>>>>>> <A HREF="http://postgis.refractions.net/mailman/listinfo/postgis-devel">http://postgis.refractions.net/mailman/listinfo/postgis-devel</A><BR>
>>>>>>>> -----------------------------------------<BR>
>>>>>>>> The substance of this message, including any attachments, may be<BR>
>>>>>>>> confidential, legally privileged and/or exempt from disclosure<BR>
>>>>>>>> pursuant to Massachusetts law. It is intended<BR>
>>>>>>>> solely for the addressee. If you received this in error, please<BR>
>>>>>>>> contact the sender and delete the material from any computer.<BR>
>>>>>>>> _______________________________________________<BR>
>>>>>>>> postgis-devel mailing list<BR>
>>>>>>>> postgis-devel@postgis.refractions.net<BR>
>>>>>>>> <A HREF="http://postgis.refractions.net/mailman/listinfo/postgis-devel">http://postgis.refractions.net/mailman/listinfo/postgis-devel</A><BR>
>>>>>>>><BR>
>>>>>>>><BR>
>>>>>>>><BR>
>>>>>>><BR>
>>>>>>> --<BR>
>>>>>>> Martin Davis<BR>
>>>>>>> Senior Technical Architect<BR>
>>>>>>> Refractions Research, Inc.<BR>
>>>>>>> (250) 383-3022<BR>
>>>>>>><BR>
>>>>>>> _______________________________________________<BR>
>>>>>>> postgis-devel mailing list<BR>
>>>>>>> postgis-devel@postgis.refractions.net<BR>
>>>>>>> <A HREF="http://postgis.refractions.net/mailman/listinfo/postgis-devel">http://postgis.refractions.net/mailman/listinfo/postgis-devel</A><BR>
>>>>>>><BR>
>>>>>>><BR>
>>>><BR>
>>>> _______________________________________________<BR>
>>>> postgis-devel mailing list<BR>
>>>> postgis-devel@postgis.refractions.net<BR>
>>>> <A HREF="http://postgis.refractions.net/mailman/listinfo/postgis-devel">http://postgis.refractions.net/mailman/listinfo/postgis-devel</A><BR>
>>>><BR>
>>>><BR>
>>><BR>
>>> --<BR>
>>> Martin Davis<BR>
>>> Senior Technical Architect<BR>
>>> Refractions Research, Inc.<BR>
>>> (250) 383-3022<BR>
>>><BR>
>>> _______________________________________________<BR>
>>> postgis-devel mailing list<BR>
>>> postgis-devel@postgis.refractions.net<BR>
>>> <A HREF="http://postgis.refractions.net/mailman/listinfo/postgis-devel">http://postgis.refractions.net/mailman/listinfo/postgis-devel</A><BR>
>>><BR>
>> _______________________________________________<BR>
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>> postgis-devel@postgis.refractions.net<BR>
>> <A HREF="http://postgis.refractions.net/mailman/listinfo/postgis-devel">http://postgis.refractions.net/mailman/listinfo/postgis-devel</A><BR>
>><BR>
>> ________________________________<BR>
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>> this in error, please contact the sender and delete the material from any<BR>
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