Mapserver and threading

[Frank Warmerdam]

On 9/17/05, Shawn Wallbridge <shawn at synack-hosting.com> wrote:
> I am contemplating the machine I want to run Mapserver on and I am
> trying to decide between a a couple of machines.
> 
> Has anyone run Mapserver on a 4+ CPU machine? Does it thread very well?
> 
> PostGIS will be running on a different machine (Quad Processor Sun
> e450 with 4GB of Ram, lots of SCSI disks running Solaris 10).

Shawn, 

The common way of running MapServer is as a cgi (either mapserv
itself, or a mapscript cgi).  In this form, each cgi request will run on 
a single CPU but several requests can be effectively serviced at a 
time. 

It is also possible to run MapServer in a multi-threaded way.  I 
would have to say that this is not so widely used, and consequently
somewhat risky. 

So, if you are running as a cgi, then you will be able to support more
requests on a multi-cpu system than on a single cpu system assuming
you find things are cpu bound.  Of course, in many cases things are
really input/output or memory bound in which case the multi-cpus will
give relatively little benefit. 

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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