From owner-freebsd-stable Thu May 9 7:19:50 2002 Delivered-To: freebsd-stable@freebsd.org Received: from sysadmin.chi.ubsw.com (sysadmin.chi.ubswarburg.com [146.180.1.66]) by hub.freebsd.org (Postfix) with ESMTP id DB4C337B403 for ; Thu, 9 May 2002 07:19:43 -0700 (PDT) Received: from devin by sysadmin.chi.ubsw.com with local (Exim 3.12 #2) id 175olg-0002NT-00; Thu, 09 May 2002 09:19:40 -0500 Date: Thu, 9 May 2002 09:19:39 -0500 (CDT) From: Tod McQuillin X-X-Sender: devin@sysadmin To: Erik Trulsson Cc: MikeM , Subject: Re: Steadily increasing memory usage on a lightly loaded server In-Reply-To: <20020509140719.GA28169@student.uu.se> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thu, 9 May 2002, Erik Trulsson wrote: > The memory that is marked as 'Inactive' is also available for allocation > just as the 'Free' memory. In practice you can just add together the > 'Inactive' and the 'Free' memory to get the total of free memory. Not quite -- if I understand it correctly, 'Inactive' is still part of a running process's address space (or buffer cache) but has not had it's page-used bit turned on since the last time it was cleared. > The 'Inactive' memory contains data that *can* be reused (such as the > code for programs that has recently been run) but that can also be > thrown away without further notice if necessary. I think you are thinking of 'Cache', not 'Inactive'. Pages in the inactive queue are still dirty, so they must be paged out before they can be reused. 'Cache' pages are clean, so they can be reused at any time. See http://www.freebsd.org/doc/en_US.ISO8859-1/articles/vm-design/x78.html for details. > I wouldn't worry about swap being used either. FreeBSD tends to write > some things to swap before it is actually *necessary* to do it. Yup. Swap usage can actually be a good optimisation, not a sign of memory shortage. -- Tod McQuillin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message