   (hl-line-mode 1)
   (toggle-truncate-lines 1)
   (setq font-lock-defaults ovirt-log-analyzer-font-lock-keywords)
+  (setq buffer-invisibility-spec '(yes))
   (ovirt-log-analyzer-process))
 
 (provide 'ovirt-log-analyzer)

    (while (not (eobp))
      (unless (funcall filter-function)
        (let ((o (make-overlay (line-beginning-position) (1+ (line-end-position)))))
          (overlay-put o 'invisible t)
          (overlay-put o 'ovirt-log-analyzer-filter t)))
      (forward-line))))

(defun ovirt-log-analyzer-filter-by-text (text)
  (message "Filtering by %s" text)
  (ovirt-log-analyzer-filter-by-function (lambda () (search-forward text (line-end-position) t))))

(defun ovirt-log-analyzer-filter-by-property (property value)
  (message "Filtering by %s" value)
  (ovirt-log-analyzer-filter-by-function (lambda () (equal (get-char-property (point) property) value))))

(defun ovirt-log-analyzer-filter ()
  (interactive)

                ;; generic tag without special handling
                )
               (t
                (add-to-list 'unknown-tags tag))))
            (when visible-tags
              (goto-char tag-beg)
              (while (re-search-forward "\\(Host\\|VM\\)=\\([^; |]*\\)" tag-end t)
                (let ((entity (match-string 1))
                      (value (match-string 2))
                      (o (make-overlay (match-beginning 0) (match-end 0))))
                  (overlay-put o 'invisible 'no)
                  (overlay-put o 'face 'font-lock-variable-name-face)
                  (overlay-put o 'before-string " ")
                  (overlay-put o 'priority 10)
                  (cond
                   ((string= entity "Host")
                    (overlay-put o 'ovirt-log-analyzer-host value))
                   ((string= entity "VM")
                    (overlay-put line-overlay 'ovirt-log-analyzer-vm value)))
                  (goto-char (overlay-end o)))))
            (overlay-put tag-overlay 'invisible 'yes)))
        (forward-line))
      (when (> max-file-field-length 0)
        (goto-char (point-min))
