There are plans to organize was a containers mini-summit at the [http://www.linuxsymposium.org/2008/ OLS'08]. This page is served for organizing this mini-summit. Feel free to editevent.
'''When''': before 23rd 22nd of July 2008 (on a day before the OLS itself), 8:30-16:30<br/>'''Where''': Ottawa, ON, Canada, Novotel Hotel (Albion A). == Notes == For the notes from the mini-summit, '''see [[Containers/Mini-summit 2008 notes]].'''
== Proposal ==
A The mini-summit proposal to be sent to OLS organizers. See ; '''see [[{{PAGENAME}}/Proposal|proposal]]'''.
== Topics to discuss ==
* device Device accessibility cgroup (maybe with remap ability)* ttysTTYs* syslogSyslog* checkpointCheckpoint/restart* Memory controllers
* more?..
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# Kir Kolyshkin
# Pavel Emelyanov
# Denis Lunev
# Serge Hallyn
# Dave Hansen
# Cedric Le Goater
# Daniel Lezcano
# Srivatsa Vaddagiri
# Sukadev Bhattiprolu
# Paul Menage
# Eric W. Biederman# Oren Laadan# Yamamoto Takashi# Kamezawa Hiroyuki# Benjamin Thery# Herbert Pötzl# Oleg Nesterov# Dhaval Giani# Bart Trojanowski# Joseph Ruscio# Constant Chan# Linda Knippers# Satoshi Uchida# Masahiko Takahashi# Martine Silbermann# Benoit des Ligneris# Patrick Naubert# Daisuke Nishimura# Sudhir Kumar# Munehiro Ikeda# Kamalesh Babulal# John Schulz# Poornima Nayak# Gyuil Cha# YoungHo Kim# Rob Woolley# Daniel Robbins# Jason Baron# Subrata Modak# Veerendra C# Joe MacDonald# Andrew Theurer# Myron Stowe# Peter Teoh# Ricky Liang
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== Agenda ==
TODO* Namespaces/Containers (8:30am-11am)** sysfs issues (and any /proc issues)*** uevents/hotplug** Network namespaces issues*** multiple namespaces in one process** Device namespace design?** User namespace** Additional needed namespaces*** Small namespaces ''What to do with small subsystem that might need virtualization. E.g. in openvz we have FUSE, binfmt_misc and some other small stuff virtualized. But how to merge it in mainline? Create a separate namespace for each? Mere them into one? How to call this then?''** Handling filesystem/namespace synchronization (not sure what the issue is)** Container design*** How to enter a container*** Nature of a 'container' — kernel object or userspace fiction * Cgroups+Resource management (11:30-2pm)** Cgroup implementation*** Locking (don't let cgroup_lock() become the BKL)*** Transactional attachment*** "procs" file*** User-space notification API**** Resource counter hit soft/hard limit**** Task entered/left cgroup**** OOM occurred*** Binary statistics API** Existing cgroups*** Memory (Balbir's NOTE: I would prefer to take some of this discussion to my memory controller BoF on Wednesday. Lets discuss this at the end)**** Supporting over-commit and guarantees**** Soft-limits**** Hierarchical borrowing - in kernel or userspace?**** Per-cgroup refault information?*** Kernel memory*** Device*** Memrlimit**** Some push-back over this - can we give real use cases?*** CPU scheduler** Additional cgroups and their design*** Swap (separate subsystem or merge with memory?)*** Disk I/O (several proposed designs)*** Network traffic classification*** Freezer*** Signaller*** OOM Handler** libcg - userspace explotation of control groups/resource management*** Overview so far*** Is kernel-based reclassification needed?*** Real use-cases*** Future directions * Checkpoint/Restart (2:30pm-5pm)** Documentation : Look at "See Also" section below** Goals and expectations of this summit*** identify, discuss and (if possible) agree on the general design*** identify, discuss and (if possible) agree on the technical points*** decide on priorities for different components (eg. high, medium, low) such that the final outcome is a practical road-map that would keep us busy for (at least) until the next OLS (though the "O" may change ;)** What are the problems that the linux community can solve with the checkpoint/restart ?** Preparing the kernel internals*** How we implement it without affecting long term maintainability ?*** What are the kernel subsystems, process resources and framework for CR ?*** Which pieces to target first ? The following technical points can be discussed during the mini-summit if we have time or later at the OLS. ** Checkpointing / Restarting*** Reaching a quescient point - network, processes, aio, avoiding side effects of quiesce/revive*** Checkpoint - signal handler ? syscall ? crfs ? process hierarchy, resource dependencies, system and process resources*** Restarting - New binary format handler ? converting between formats (from older kernel to newer)*** Notification to processes which explicitly wish to be notified about quiesce, checkpoint and restart - container state ? new signals ?** Determining the userspace API - Posix 1003.1m ?** Passing the kernel internal state to/from userspace - coredump like file ? swap per container ? netlinks, CR filesystem ? army of different call for the CR (proc, existing syscalls, ...)** Hopefully we can continue to discuss in the next days and get a bit of a hackfest going during OLS :) == Moderators == * Namespaces/containers: Serge Hallyn, Dave Hansen* Cgroups and resource management: Paul Menage, Balbir Singh, Dhaval Giani* Checkpoint/restart: Daniel Lezcano, Oren Laadan
== See also ==
* http://www.linuxsymposium.org/2008/cfp.php — OLS call for papers
* https://lists.linux-foundation.org/pipermail/containers/2008-January/009688.html
* http://openvz.org/pipermail/devel/2008-July/012891.html
* Checkpoint/Restart
** Zap : http://www.ncl.cs.columbia.edu/publications/usenix2007_fordist.pdf
** Metacluster : http://lxc.sourceforge.net/doc/ols2006/lxc-ols2006.pdf
** OpenVZ : [[Checkpointing and live migration]]
** Checkpoint/Restart technology : http://en.wikipedia.org/wiki/Application_checkpointing
** Virtual Servers and Checkpoint/Restart in Mainstream Linux : Sigops document
** Remote fork: http://www.cse.nd.edu/~dthain/courses/classconf/wowsys2004/talks/rfork.pdf
** Vmadump : http://bproc.sourceforge.net/c268.html
** Posix CR : http://techpubs.sgi.com/library/tpl/cgi-bin/getdoc.cgi/0650/bks/SGI_Admin/CPR_OG/sgi_html/ch03.html
** An OS services overview : http://sw-eng.falls-church.va.us/itsg/P08V31.htm
[[Category: Containers]]
[[Category: Events]]