Same problem here, though it seems it have worsen recently on 13.10 (with Firefox 25?). With 5000 bookmarks, hud-service uses one CPU at 100% all the time, with a complete freeze every-time I switch a tab or firefox's window gets the focus.
By using the BookmarkMenuHider add-on to remove the bookmarks from the menu, the CPU usage goes back to 20% the time. This can be a nice workaround for computers with relatively beefy processors. You can find the add-on there: https://addons.mozilla.org/en-US/firefox/addon/bookmarkmenuhider Finally, the "ui.use_unity_menubar = false" fix drops the CPU usage of hud-service below 1%, and Firefox experience is back to butter smooth :-) Of course the drawback is that the menu is gone from the HUD :-( -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/968533 Title: Alt-tab to Firefox sends Firefox to 100% CPU; unity-panel-service to 80% CPU and hud-service to 20-80% CPU To manage notifications about this bug go to: https://bugs.launchpad.net/unity/+bug/968533/+subscriptions -- ubuntu-bugs mailing list firstname.lastname@example.org https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs