Optimize lookup of EPSG projection codes

[dmorissette]

A few weeks ago I was doing some benchmarks with MapServer 4.10 on a mapfile
with about 10 layers in it and replacing the 10 "init=epsg:xxxx" defns with
native PROJ.4 definitions made the WMS GetCapabilities requests go from 3
hits/seconds to 12 hits/seconds (4 times faster!).

Since EPSG codes are used a lot by all OGC services, optimizing the EPSG lookup
(or caching them at a minimum) is something that would be very valuable for all
OGC service users.

[dmorissette]

Let's see if we can address this in 5.0

[dmorissette]

Ticket #1426 was marked as duplicate of this ticket.

[dmorissette]

I have started a thread discussing possible solutions on the PROJ list:  http://lists.maptools.org/pipermail/proj/2007-August/003002.html

[hobu]

This one isn't happening for 5.0, right?

[dmorissette]

Depending on the outcome of the discussion on the PROJ list the issue may be fixed in 5.0 with very little or no changes to the code, it may end up only being a documentation issue (e.g. use PROJ v x.y with threads option enabled) so I'll wait until the last minute before pusing this to 5.2.

[warmerdam]

I have added memory caching of init definitions in PROJ.4, primarily in:

 http://trac.osgeo.org/proj/changeset/1542

This should appear in the PROJ 4.7.0 release in the fairly near future I hope.