From owner-freebsd-hackers@FreeBSD.ORG Fri Feb 24 16:03:26 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A24C2106564A for ; Fri, 24 Feb 2012 16:03:26 +0000 (UTC) (envelope-from freebsd-hackers@m.gmane.org) Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) by mx1.freebsd.org (Postfix) with ESMTP id 582058FC08 for ; Fri, 24 Feb 2012 16:03:26 +0000 (UTC) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1S0xc5-0002lW-Ns for freebsd-hackers@freebsd.org; Fri, 24 Feb 2012 17:03:17 +0100 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 24 Feb 2012 17:03:17 +0100 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Fri, 24 Feb 2012 17:03:17 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-hackers@freebsd.org From: Ivan Voras Date: Fri, 24 Feb 2012 17:03:00 +0100 Lines: 40 Message-ID: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig1753D0189C70973BDF8F1B3F" X-Complaints-To: usenet@dough.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:10.0) Gecko/20120213 Thunderbird/10.0 X-Enigmail-Version: 1.3.5 Subject: Tracking memory, PCI(-E) bus usage? X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Feb 2012 16:03:26 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig1753D0189C70973BDF8F1B3F Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable This is mostly idle wanderings than anything useful, but I've just redirected an application which creates a lot of temporary data to a tmpfs mount point and I'm happily observing disk bandwidth dwindling from a sustained many dozens of MB/s to merely hundreds of KB/s, which is the value the system was designed for. That got me thinking that I would also be happy if I could observe the bandwidth used by the memory file system, and even memory in total, and by extension, the traffic on various busses. So this is the question for people who twiddle with the hardware level: is there a way in which those quantities could be tracked in real-time? For the memory, I guess it would depend on the memory controller, but even memory controllers are built-in in recent CPUs, which means there could be a way. I'm vaguely recalling that PCI-E (at least) works in some kind of packet-based transaction mode so it seems possible that it could also offer some metrics. --------------enig1753D0189C70973BDF8F1B3F Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.18 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk9HtLQACgkQldnAQVacBcgF/gCePk6ZRdQ7QIo4pg9ymvOoZNmI tQ8AoKjMFnP77TvUx2oG3TyNIPywAurR =WJag -----END PGP SIGNATURE----- --------------enig1753D0189C70973BDF8F1B3F--