Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 21 May 2013 11:40:30 -0700
From:      Charles Swiger <cswiger@mac.com>
To:        Dmitry Sivachenko <trtrmitya@gmail.com>
Cc:        questions@freebsd.org
Subject:   Re: RES column in top(1) output
Message-ID:  <B12E243B-4D87-4EC5-950D-B78C82B9BE45@mac.com>
In-Reply-To: <24044FD7-4E2A-493F-B0CE-701C3A73169F@gmail.com>
References:  <24044FD7-4E2A-493F-B0CE-701C3A73169F@gmail.com>

Next in thread | Previous in thread | Raw E-Mail | Index | Archive | Help
On May 21, 2013, at 11:03 AM, Dmitry Sivachenko <trtrmitya@gmail.com> =
wrote:
> Hello,
>=20
> Can you please explain me the meaning of RES column in top(1) output:
> as far as I understand from man-page, it is resident portion of the =
process, that is the amount of memory process takes from RAM.

Yes, that's the definition.

> But I get:
>=20
> Mem: 55G Active, 23G Inact, 11G Wired, 3729M Cache, 9838M Buf, 97M =
Free
> Swap: 49G Total, 14M Used, 49G Free
>=20
>=20
>  PID USERNAME      THR PRI NICE   SIZE    RES STATE   C   TIME   WCPU =
COMMAND
> 93273 username        103  52    0   141G   115G uwait  22  25:37 =
19.82% XXX
>=20
> So I have a machine with 96GB of RAM, no swap is used and my process's =
resident size is 115G (more than physical memory).

Memory that has been allocated but not written to is associated with the =
process address space in terms of accounting, but does not actually =
consume physical memory.  There's also copy-on-write memory (used for =
the program executable code itself, which is also typically also marked =
read-only), mmap()ing big sparse files or device special files like a =
video framebuffer (ie, an X11 server), and probably a few other things =
which can reserve lots of resident memory without actually consuming =
physical memory.

Regards,
--=20
-Chuck




Want to link to this message? Use this URL: <http://docs.FreeBSD.org/cgi/mid.cgi?B12E243B-4D87-4EC5-950D-B78C82B9BE45>