Bug 61950 [Markers] Images being created twice potentially
org.eclipse.ui.views.internal is using a static called ImageFactory which has it's own ImageRegistry. It should use JFaceResources.getImageRegistry to be sure that images are not being created twice (Image creation can be very expensive). I am not sure that this is a problem currently with performance but it could add to start up time.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/FieldPriority.java
return null;
        }
        try {
            int priority = ((TaskMarker) obj).getPriority();
            if (priority == IMarker.PRIORITY_HIGH) {
                return ImageFactory.getImage(HIGH_PRIORITY_IMAGE_PATH);
            }
            if (priority == IMarker.PRIORITY_LOW) {
                return ImageFactory.getImage(LOW_PRIORITY_IMAGE_PATH);
            }
        } catch (NumberFormatException e) {
            return null;
        }
        return null;
    }
    /*
     *  (non-Javadoc)
     * @see org.eclipse.ui.views.markers.internal.IField#compare(java.lang.Object, java.lang.Object)
     */
    public int compare(Object obj1, Object obj2) {
        if (obj1 == null || obj2 == null || !(obj1 instanceof TaskMarker)
                || !(obj2 instanceof TaskMarker)) {
            return 0;
        }
        int priority1 = ((TaskMarker) obj1).getPriority();
        int priority2 = ((TaskMarker) obj2).getPriority();
        return priority1 - priority2;
    }
}