Actually, I tried isolating the other Layers and benchmarking again. It turns out the 1st Layer (Areas) I tried is the most complex which is why the response time was roughly the same. I tried a Boundary layer and render time was about 2 seconds.<div>
<br></div><div>Jason<br><div><br><br><div class="gmail_quote">On Wed, Jan 11, 2012 at 10:44 AM, Jason Lee <span dir="ltr"><<a href="mailto:jaslee.st@gmail.com">jaslee.st@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<span>Hi,</span><div>I have mod_tile running on a dedicated Linux server (Ubuntu 11.04, 24GB RAM, 8 virtual QuadCore i7 processors) and generating some custom maps. I am using ab (Apache Bench) to benchmark its performance when rendering new tiles (at zooms 17-18, 1 concurrent x 1 run, clearing cache each time) and getting time around 10,000 ms (10 secs) per tile. Thereafter it is very quick (100ms) because it is cached.</div>
<div><br></div><div>Ten seconds does sound quite slow and I was wondering what can be done to improve it. Just out of curiosity, I tried disabling all the 7 Layers except for 1 Layer in the Mapnik stylesheet, so the rendering requires a lot less db querying and map rendering - but I'm still getting 10 seconds performance. This would suggest that the performance bottleneck is not related to the mapnik backend.</div>
<div><br></div><div>I've also played around with increasing the NUM_THREADS=3 to 32 in the renderd.conf, but still no significant performance improvement when rendering a fresh tile. Any ideas or pointers would be welcome. Thanks</div>
<span class="HOEnZb"><font color="#888888">
<div><br></div><div>Jason</div>
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