From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman) Subject: Re: c/r, time, and virtualization Date: Sat, 25 Jul 2009 00:26:50 -0700 Message-ID: References: <4A6A93FC.7090209@librato.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4A6A93FC.7090209-RdfvBDnrOixBDgjK7y7TUQ@public.gmane.org> (Oren Laadan's message of "Sat\, 25 Jul 2009 01\:11\:24 -0400") List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Oren Laadan Cc: Linux Containers , Jeff Dike List-Id: containers.vger.kernel.org Oren Laadan writes: > Hi, > > I wonder what's that status of time namespaces and virtual time(rs) ? > > http://lwn.net/Articles/180375/ - "virtual time" coverage in LWN (2006) > http://lkml.org/lkml/2006/4/13/172 - patchset and thread on LKML > http://lwn.net/Articles/249080/ - kernel summit 2007 - containers > > It will be handy for c/r of timers (posix-timers) that I'm working on. > > A couple of obstacles off the top of my head: > > - Lack of clone flags -- we can use clone_with_pids() for that. > > - Fast gettimeofday() via vdso -- perhaps a vdso page per time-ns > (containing the necessary deltas). > > Is anyone working on it ? I proposed it, for the reason you care. I have thought about the semantics. But I haven't gotten as far as implementing something. I will be happy to bounce ideas off, and review code when I have a few seconds free. Eric