Path: utzoo!utgpu!watmath!att!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!zephyr.ens.tek.com!orca!frip!andrew From: andrew@frip.WV.TEK.COM (Andrew Klossner) Newsgroups: comp.arch Subject: TLB traffic reports (was Re: Cycle Counter) Message-ID: <4221@orca.WV.TEK.COM> Date: 14 Aug 89 20:09:02 GMT References: <559@halley.UUCP> <5818@pt.cs.cmu.edu> Sender: nobody@orca.WV.TEK.COM Distribution: comp Organization: Tektronix, Wilsonville, Oregon Lines: 15 [] "When a programmer suspects thrashing, the average OS can help by reporting paging rates, task switch counts, interrupt load, ethernet packets, and so on. The OS typically is unable to report on cache traffic or on TLB traffic." An OS hacker could get most of the way there without hardware assist by making regular (once per clock tick?) sweeps through the page tables, noting and clearing the "page used" bits and flushing the TLB. For example, it wouldn't take more than a couple of days to fit something like this into Unix system V, including the statistic reporting utility. -=- Andrew Klossner (uunet!tektronix!frip.WV.TEK!andrew) [UUCP] (andrew%frip.wv.tek.com@relay.cs.net) [ARPA]