[Mapserver-users] connection pooling

[Jan Hartmann]

David Mitchell wrote:
> 
> So this means there is no connection pooling support for postgis?
> 
> 

I haven't checked the latest CVS version, but at the beginning of this 
year the connection pooling mechanism had not yet been extended to 
PostGIS. It doesn't matter very much however, as connection pooling 
gives practically no performance gain here. PostgreSQL is very efficient 
in connecting to a database, so the difference between creating a 
connection for every layer or just connecting once for the whole mapfile 
is very small. It would be nice if connection pooling would be 
implemented for PostGIS (it's only a dozen lines or so), but it is not 
essential at all. Yet, unless there are drawbacks I don't know about, 
perhaps someone from Refractions could file a bug, to remind them of it 
on a rainy day with nothing else to do.

It is different for SDE and Oracle. SDE has been done by Steve Lime last 
year, resulting in real performance gain, as I heard. For Oracle it 
would be a really important addition. I don't know if there are people 
working on the Oracle interface at the moment (I vaguely remember having 
read that they had gone AWOL). If they have returned, I would be happy 
to assist.

BTW: connection pooling is not as important for databases as for static 
maps. With a database, you don't have to return separate layers, you can 
also return information in a single layer, dynamically produced by a 
subquery.

Jan


Jan