Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 24 Jan 2011 20:07:25 -0700
From:      Chad Perrin <perrin@apotheon.com>
To:        FreeBSD Questions <freebsd-questions@freebsd.org>
Subject:   Re: more CPU being used than I have (?)
Message-ID:  <20110125030725.GA62670@guilt.hydra>
In-Reply-To: <1295917366.59721.2.camel@main>
References:  <20110124235740.GA62134@guilt.hydra> <1295917366.59721.2.camel@main>

next in thread | previous in thread | raw e-mail | index | archive | help

--bp/iNruPH9dso1Pn
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Tue, Jan 25, 2011 at 01:02:46AM +0000, Craig Butler wrote:
> On Mon, 2011-01-24 at 16:57 -0700, Chad Perrin wrote:
> > I'm running a two-core laptop that, once in a great while, shows
> > approximately 250% CPU usage by a single process in top.  How exactly
> > does that work?
> >=20
> > Note: It's not entirely surprising that this particular process is
> > consuming a lot of resources.  It's just surprising to me that it's
> > consuming more than CPUs * 100%.
>=20
> Hi Chad
>=20
> Its to do with top using weighted CPU percentage... for some reason this
> show peaks as more usage than 100% -- maybe something to do with the top
> averaging out over a specific time.
> I find that raw CPU mode gives a more accurate representation.=20
>=20
> raw mode is toggled by passing the -C argument to top.

Do you have a reference to a relatively simple explanation of how that
weighting works (and why)?

--=20
Chad Perrin [ original content licensed OWL: http://owl.apotheon.org ]

--bp/iNruPH9dso1Pn
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.14 (FreeBSD)

iEYEARECAAYFAk0+Pm0ACgkQ9mn/Pj01uKVCdgCgv9cvXg/TTYLhL7cmQfa3thnO
bWIAoL1FfqVgBT3X4AeBmjdcc3TPUyBv
=mPjG
-----END PGP SIGNATURE-----

--bp/iNruPH9dso1Pn--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20110125030725.GA62670>