[mapserver-users] WMS Orthophoto performance

[Andy Colson]

On 8/2/2010 5:06 AM, Cédric MOULLET wrote:
> Hello,
> We've got a 150 GB ECW dataset (aerial imagery) and the LAYER
> configuration uses a TILEINDEX.
> We can observe a WMS request time of about 3 seconds (on a server with
> this configuration: 7.5 GB RAM, 4 core, 64 bits / MapServer 5.4.3).
> I'd like to know if 3 seconds is considered as a normal response time
> for this kind of WMS request.
> What could be done in order to improve this performance (I'm aware of
> http://www.mapserver.org/optimization/raster.html) ?
> Thanks !
> Cédric
>

Wow, that's a big file.  Is that all in one file?  I dont really know 
the answer, I've never used anything over 4 gig, but I do have a few 
questions:

1) I assume you are IO bound, do you have this on a raid, or something 
with fast IO?  Can you check to see if you are CPU bound or IO bound?

2) if it is one big file, how would you feel about trying it broken up 
into smaller files?

-Andy