On Wed, 2011-01-05 at 18:54 +0100, Andrea Aime wrote: > On Wed, Jan 5, 2011 at 6:30 PM, Gabriel Roldán <[email protected]> wrote: > > Hi all, > > > > as per http://jira.codehaus.org/browse/GEOS-4163, there's now the > > possibility of directly integrating GWC with the regular WMS, providing > > WMS-C capabilities directly out of the GeoServer WMS: > > > > * There's the possibility to enable direct GWC WMS integration > > through the UI (disabled by default) > > Nice > > > * The gwc module intercepts regular WMS calls, and if direct WMS > > integration is enabled, it will check whether the request comes > > with TILED=true AND matches a cached tile, and if to, will serve > > the cached copy. Otherwise it defers to the regular WMS call. > > I see this has been done using Spring AOP, good. > I hope this means it's still possible to remove all GWC related jars > from GeoServer > and have it working fine.
right. > This is imperative for the WMS performance shootout, always removed GWC > entirely > to prove that no caching was going on (or was possible) in the tests. yes, it was a design decision to keep it decoupled. > > Also, there is a concern that GWC embedded in GeoServer can turn into a disk > killing bomb: the tile caches can become rather large, as an administrator I'd > like to have GWC around only if I really need it, and to configure it tightly > to avoid misuse. > The default GWC configuration instead does not prevent that, which is one > reason > why I normally get rid of it unless I'm actually going to use it and > configure it > in detail (btw, is the quota functionality ever going to be included > in GeoServer > GWC? That's something every conscious admin should configure, along with > the other service limits). Agreed. The GWC integration story so far has been kind of weak IMHO. I'm working towards improving it. Started with truncating the cache based on transaction's affected bounds, etc. Now this direct WMS integration, which's disabled by default. And next diskquota may arrive late this week or the next top, with ability to set a global cache quota limit and an expiration policy so that tiles least used get removed to keep up with the quota. A per-layer quota limit is also possible, but configuring that from the GeoServer UI is part of a wider plan, so it'll take longer to arrive. > > > * if the getcapabilities request comes with TILED=true, the gwc > > module contributes the WMS-C VendorSpecificCapabilities, adding > > an internal DTD definition for TileSet/Resolutions/etc and one > > TileSet per cached layer/CRS/output format combination. > > * the GetCapabilities namespace vendor specific parameter is > > respected, so that if the request comes with namespace=topp, > > only TileSets for layers in the topp namespace will be added. > > Nice and nice. > > > Note, however, that the default geoserver layer preview demos won't hit > > the cache because they calculate the tile origin based on the layer's > > bounding box, which generally doesn't match the GWC's gridset tile > > origin. But the WMS caps providing the WMS-C extended capabilities > > (specifically the TileSet definitions) do make it possible to create OL > > apps that match the layer's gridsets. > > > > It would be nice to have the layer preview match the gwc gridsets by > > default, but so far it's not such an easy task as the openlayers map > > output format is decoupled from the gwc module. > > I guess it would be nice, but it would be better to do that only if GWC > is around, and without introducing a dependency. Some sort of > extension point? right. Reason why I didn't make it so far, just ran out of time to keep things so nice and didn't want to hack in. > Wondering if the extension point that is used to declare the tilesets > extensions in the capabilities could be also used to drive the OL > preview configuration. Guess it has to be a separate one. That one is intended for capabilities only and used by the inspire and gwc so far. Thanks for the feedback Andrea. Gabriel. > > Cheers > Andrea > > ----------------------------------------------------- > Ing. Andrea Aime > Senior Software Engineer > > GeoSolutions S.A.S. > Via Poggio alle Viti 1187 > 55054 Massarosa (LU) > Italy > > phone: +39 0584962313 > fax: +39 0584962313 > > http://www.geo-solutions.it > http://geo-solutions.blogspot.com/ > http://www.linkedin.com/in/andreaaime > http://twitter.com/geowolf > > ----------------------------------------------------- -- Gabriel Roldan [email protected] Expert service straight from the developers ------------------------------------------------------------------------------ Learn how Oracle Real Application Clusters (RAC) One Node allows customers to consolidate database storage, standardize their database environment, and, should the need arise, upgrade to a full multi-node Oracle RAC database without downtime or disruption http://p.sf.net/sfu/oracle-sfdevnl _______________________________________________ Geoserver-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geoserver-devel
