Re: [jboss-dev] Improving scanning performance

Ales Justin wrote: > All of this already exists. ;-) > >> * You should have a AnnotationScanner deployer that scans jars for >> annotations and puts an annotation database somewhere in memory that >> other deployers can reference. (This might already exist, I don't >> know). > > It is called AnnotationEnvironment, and it's part of the deployment's > attachments. > > It's already used to help Metadata get annotation info. > But how it's done in Metadata is bad/wrong. > >> * If a file META-INF/no.scan exists in a jar, then don't scan the >> file. This allows libraries to exclude themselves from scanning. >> >> * If a file META-INF/scan.only exists it will contain a newline >> delimited list of class names to scan. Only scan those class names. > > This is called jboss-scanning.xml. > - http://www.jboss.org/community/wiki/JBoss5custommetadatafiles I hacked my local trunk (6) build to use jboss-scanning.xml and don't see much of an impact on boot performance. Prior to the jboss-scanning.xml changes, we were scanning about 600 classes for annotations. After the changes, we scan zero classes for annotations (as per trace logging in o.j.d.p.a.GenericAnnotationResourceVisitor). My local timings are: