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<div class="Normal"><span style='font-size: 10pt; '>Hi Andi</span></div>
<br>
<div class="Normal"><span style='font-size: 10pt; '>> What exactly do you
mean by "rendering straight from postgis"? What
</span><br><span style='font-size: 10pt; '>> software is rendering straight
from Postgis? UMN Mapserver, or what
</span><br><span style='font-size: 10pt; '>> other renderer? Or your own
renderer?</span><br><span style='font-size: 10pt; '>No, "straight from postgis"
means adding the layer in QGIS from postgis. I save this qgis project and make
it available as WMS. Since there is only QGIS (as renderer) involved I thought
there would not be a big performance difference. Ok, there is apache who is
handling the cgi request but that won't take 4 seconds.</span></div>
<br>
<div class="Normal"><span style='font-size: 10pt; '>> There are some
performance bottlenecks regarding clipping of
</span><br><span style='font-size: 10pt; '>> larger/more
</span><br><span style='font-size: 10pt; '>> complex polygons. Marco can tell
you more.</span><br><span style='font-size: 10pt; '>I don't think it's a
clipping issue since it's fast when adding the same layer 'straight from
postgis' :) So there must be some additional work when making a detour.
</span></div>
<br>
<div class="Normal"><span style='font-size: 10pt; '>regards</span><br><span style='font-size: 10pt; '>Stefan</span></div>
<br>
<div class="Normal"><span style='font-size: 10pt; '>>
</span><br><span style='font-size: 10pt; '>>
Andreas</span><br><span style='font-size: 10pt; '>>
</span><br><span style='font-size: 10pt; '>> On 3/20/11 2:44 PM, Ziegler
Stefan wrote:</span><br><span style='font-size: 10pt; '>> >
Hi</span><br><span style='font-size: 10pt; '>>
></span><br><span style='font-size: 10pt; '>> > I have some questions
concerning the performance of qgis
</span><br><span style='font-size: 10pt; '>> mapserver: Using layers with a
small amount of polygons I do </span><br><span style='font-size: 10pt; '>>
not see a big difference between rendering the same layer
</span><br><span style='font-size: 10pt; '>> straight from postgis and from
local qgis mapserver </span><br><span style='font-size: 10pt; '>>
installation. For a layer with some 400'000 polygons it takes
</span><br><span style='font-size: 10pt; '>> approx. 4 seconds from qgis
mapserver (even for large scales </span><br><span style='font-size: 10pt; '>>
with only some polygons to render). But it only takes some
</span><br><span style='font-size: 10pt; '>> fractions of a second when the
layer is rendered straight </span><br><span style='font-size: 10pt; '>> from
postgis (and growing with smaller scales -> more
polyons).</span><br><span style='font-size: 10pt; '>>
></span><br><span style='font-size: 10pt; '>> > Everything is running
on a dual core laptop. So there </span><br><span style='font-size: 10pt; '>>
should be no big download bottleneck. No special styles are
</span><br><span style='font-size: 10pt; '>> applied to the layers (just a
simple fill and an outline). </span><br><span style='font-size: 10pt; '>> Are
there some requests in addition to "GetMap"? Or what's
</span><br><span style='font-size: 10pt; '>> responsible for this big
difference?</span><br><span style='font-size: 10pt; '>>
></span><br><span style='font-size: 10pt; '>> >
regards</span><br><span style='font-size: 10pt; '>> >
Stefan</span><br><span style='font-size: 10pt; '>>
></span><br><span style='font-size: 10pt; '>> > Mit freundlichem
Gruss</span><br><span style='font-size: 10pt; '>> > Stefan
Ziegler</span><br><span style='font-size: 10pt; '>> > Leiter amtliche
Vermessung</span><br><span style='font-size: 10pt; '>>
></span><br><span style='font-size: 10pt; '>> > Amt für
Geoinformation</span><br><span style='font-size: 10pt; '>> >
Rötistrasse 4</span><br><span style='font-size: 10pt; '>> > 4501
Solothurn</span><br><span style='font-size: 10pt; '>> > 032 627 75
96</span><br><span style='font-size: 10pt; '>> >
_______________________________________________</span><br><span style='font-size: 10pt; '>>
> Qgis-user mailing list</span><br><span style='font-size: 10pt; '>> >
Qgis-user@lists.osgeo.org</span><br><span style='font-size: 10pt; '>> >
http://lists.osgeo.org/mailman/listinfo/qgis-user</span><br><span style='font-size: 10pt; '>>
</span><br><span style='font-size: 10pt; '>>
_______________________________________________</span><br><span style='font-size: 10pt; '>>
Qgis-user mailing list</span><br><span style='font-size: 10pt; '>>
Qgis-user@lists.osgeo.org</span><br><span style='font-size: 10pt; '>>
http://lists.osgeo.org/mailman/listinfo/qgis-user</span><br><span style='font-size: 10pt; '>>
</span></div>
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