Major Starting Forge on Fedora 21 produces the following error:
WARNING: File monitoring could not be started. 16:41:20 java.io.IOException: User limit of inotify instances reached or too many open files 16:41:20 at sun.nio.fs.LinuxWatchService.<init>(LinuxWatchService.java:64) 16:41:20 at sun.nio.fs.LinuxFileSystem.newWatchService(LinuxFileSystem.java:47) 16:41:20 at org.jboss.forge.furnace.impl.FurnaceImpl.<init>(FurnaceImpl.java:152) 16:41:20 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 16:41:20 at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) 16:41:20 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 16:41:20 at java.lang.reflect.Constructor.newInstance(Constructor.java:422) 16:41:20 at java.lang.Class.newInstance(Class.java:442) 16:41:20 at org.jboss.forge.furnace.se.FurnaceFactory.getInstance(FurnaceFactory.java:63) 16:41:20 at org.jboss.tools.forge.core.furnace.FurnaceProvider.createFurnace(FurnaceProvider.java:78) 16:41:20 at org.jboss.tools.forge.core.furnace.FurnaceProvider.startFurnace(FurnaceProvider.java:110) 16:41:20 at org.jboss.tools.forge.core.furnace.FurnaceRuntime.start(FurnaceRuntime.java:80) 16:41:20 at org.jboss.tools.forge.ui.util.ForgeHelper$1.runInWorkspace(ForgeHelper.java:52) 16:41:20 at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:39) 16:41:20 at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
Forge then refuses to start properly, Eclipse gets stuck on the launching forge progress dialog. The inotify watch limit is set to default (8192 I think) which really should be enough.
So far we established, that this happens on Fedora 21 or occasionally on 20 (which is not supported anymore).
