[mapserver-users] How to make MapServer WMS super fast?

[Rahkonen Jukka]

Hi,

This requirement comes from the implementing rules of European Union's INSPIRE directive, so is conserns potentially hundreds of organizations all over Europe. Savings in getting the required speed with a single server would be great. In addition, it is a great challenge for MapServer that is said to be fast :)

-Jukka-



> -----Alkuperäinen viesti-----
> Lähettäjä: Frank Warmerdam [mailto:warmerdam at pobox.com] 
> Lähetetty: 12. joulukuuta 2008 17:30
> Vastaanottaja: Rahkonen Jukka
> Kopio: mapserver-users at lists.osgeo.org
> Aihe: Re: [mapserver-users] How to make MapServer WMS super fast?
> 
> Rahkonen Jukka wrote:
> > Hi,
> >  
> > Are there any effective tricks for making MapServer to 
> Top-Fuel class?  
> > We have now a typical ms4w installation on a rather good server 
> > platform with SCSI drives and 2 four-core processors running on 
> > Windows
> > 2003 server. Our images are tiled, uncompressed geotiffs with 
> > overviews, vector sample data set is shapefile with shptree 
> index.  I 
> > have a shortened epsg file and my mapfile is extra short. 
> Bandwith is 
> > not the limit. We are getting out now about 450 orthoimage pictures 
> > per minute (size 500 by 500 pixels) and 550 pictures from 
> the vector 
> > layer in png24 image format.  I consider that rather good, 
> but we are 
> > required to reach 20 images per second, thus 1200 images 
> per minute or 
> > 0.05 seconds per image.  I wonder if anybody has tuned 
> MapServer that far.
> >  
> > I am willing to try however exotic solutions to reach the 20 WMS 
> > output images/second goal if somebody could suggest me what to try 
> > next.  In our system there seems to be about 0.1 second 
> ballast with 
> > WMS getMap requests and I cannot get any faster response 
> even if I try 
> > with on empty data layer with nothing to render.  Have 
> anybody tried 
> > to keep mapfile,  epsg-file or even tileindex files in RAM drive?
> >  
> > Having about 20 parallel users seems to be optimal for our 
> server and 
> > if I drive just WMS getCapabilities request against my 
> mapfile I can 
> > get about 1300 responses per minute.  That leads me to 
> think that 1200 
> > rendered images per minute might be possible to reach with 
> optimal set-up.
> 
> Jukka,
> 
> I'd suggest you come to the TO Code Sprint and help us fine 
> tune performance!
> 
>    http://wiki.osgeo.org/wiki/Toronto_Code_Sprint_2009
> 
> More seriously, I have had the impression that some of the 
> "everything but the kitchen sink" distributions like MS4W, 
> FWTools and OSGeo4W have somewhat significant startup 
> overhead - possibly due to the number of DLLs being loaded at 
> startup.  You might look into a custom building a "lite" 
> version of mapserver and see if that helps.
> 
> As someone else noted, fastcgi will also let you skip such 
> startup costs on a per request basis.
> 
> But honestly, why not just buy another damn server?  Isn't 
> your time worth something!
> 
> Best regards,
> -- 
> ---------------------------------------+----------------------
> ----------
> ---------------------------------------+------
> I set the clouds in motion - turn up   | Frank Warmerdam, 
> warmerdam at pobox.com
> light and sound - activate the windows | http://pobox.com/~warmerdam
> and watch the world go round - Rush    | Geospatial 
> Programmer for Rent
> 
>