From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olaf Hering Subject: Re: [PATCH 00/18] xenpaging changes for 4.0 Date: Fri, 22 Oct 2010 10:55:42 +0200 Message-ID: <20101022085542.GA10115@aepfle.de> References: <20101015141202.309585877@aepfle.de> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Dan Magenheimer Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org On Fri, Oct 15, Dan Magenheimer wrote: > Hi Olaf -- > > Since you have obviously become an expert user of xenpaging, > any chance you could write brief how-to documentation for it > and maybe add a file to xen.hg/docs/misc? This is a first draft. Subject: xenpaging: (sparse) documenation Write up some sparse documentation about xenpaging usage. Signed-off-by: Olaf Hering --- docs/misc/xenpaging.txt | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) --- /dev/null +++ xen-4.0.1-testing/docs/misc/xenpaging.txt @@ -0,0 +1,40 @@ +Warning: + +The xenpaging code is new and not fully debugged. +Usage of xenpaging can crash Xen or cause severe data corruption in the +guest memory and its filesystems! + +Description: + +xenpaging writes memory pages of a given guest to a file and moves the +page back to the pool of available memory. Once the guests wants to +access the paged-out memory, the page is read from disk and placed into +memory. This allows the sum of all running guests to use more memory +than physically available on the host. + +Usage: + +Once the guest is running, run xenpaging with the guest_id and the +number of pages to page-out: + + mkdir /var/lib/xen/xenpaging + chdir /var/lib/xen/xenpaging + xenpaging + +To obtain the guest_id, run 'xm list'. +xenpaging will write the pagefile to the current directory. +Example with 128MB pagefile on guest 1: + + xenpaging 1 32768 + +Caution: stopping xenpaging manually will cause the guest to stall or +crash because the paged-out memory is not written back into the guest! + + + +Todo: +- implement stopping of xenpaging +- implement/test live migration + + +# vim: tw=72