Empty KML output with very large layers in version 2.1.0, not in 2.0.3
After upgrading from 2.0.3 to 2.1.0 and migrating data (all in Postgis database), we noticed that KML output for very large layers (ie that come from shapefiles from thousands of small polygons) comes out empty. On version 2.0.3 and 2.02 we had no problems downloading KMLs, although some very large (over 50MB). Each layer has its own style as sld, which is fairly simple with a legend. On 2.0.3 the KML would download and display correctly with its style. On 2.1.0, the KML request sent to Geoserver returns an empty KML with just a heading. Nothing shows up in GeoServer logs. We had to downgrade until we can solve this. I have replicated the error with many other large layers in my localhost GeoServer. Smaller layers (size, no. of features)seem to have no problem. I have both versions running on Tomcat 6. I use &mode=download at the end of the request to obtain complete KML independent from the database. With 2.0.3 KML downloads complete and opens ok, with 2.1.0=empty output. What changed from one version to another that it no loger works? How to fix this?
I noticed that cnanging the style of those huge layers to a flat, simple color does the trick, but each layer needs to have its own legend and colors. The sld (below) is simple enough so I don't know why would it cause to fail and only in version 2.1.0.
Here are the examples: