Hi devs, I am not a LXC expert but like to share some thoughts.
On Thu, Jul 11, 2013 at 2:19 PM, Lakmal Warusawithana <[email protected]>wrote: > Hi, > > > In the current Stratos, cartridge run time is a VM. With this if we want > to create a cartridge we have to do it for each and every IaaS that run > Stratos. So cartridge creator have to spend lot of time on this. And it > will be more costly when it comes to do a update of cartridges. We need to > have a way to create universal cartridges. > +1 for universal cartridges.But if the server (eg: wso2as) supports multi-tenancy already it is not good to spawn that server into some light weight container, rather we can spawn a vm(as it works in current model) or possibly LXC with more resource(we have to loose some i/o performance due to file system mounting). If the server is not multi-tenanted(eg:php) then we can spawn a container(lxc). This way we can optimize resource sharing and performance. > > The best option what I see is we can use LXC as Cartridge run time. Then > when we create a LXC cartridge it will run on top of any IaaS, and only > need Linux VM. Also it give more benefit like we can pack many cartridge > runtime in single VM which give high utilization. > Here if the implementation is abstracted(OS independent way) out such a way the container implementation is pluggable then we can run even .net cartridge also based on other implementation. > > Here auto scaling going to happen in two levels and it’s coupled with > smart auto scaling policies, will discuss separate mail thread for what > kind of auto scaling polices need for Stratos. > > > > Here I have drow some sample scenarios. Before going into detail we need > to get familiar with some terms > > - > > Partition > > We can have partition for each cartridge type. For example we can have PHP > Partition, Tomcat Partition ..etc. Partition may consist of one or many VM > and this will come from policies. (will discuss in separate mail ) > > - > > Subscription > > User can subscribe to cartridge with some unique alias, say subscription A > > - > > Cartridge Process > > Cartridge Processes are runtime environment (LXC) of subscribed cartridge. > For a one subscribed cartridge can have multiple Cartridge Processes > depending on auto scaling policies. > > To accomplish this, Stratos Cloud Controller (CC) need to expand to > support LXC management. We need to have a cartridge store and it will > store all Cartridges (LXC based images). > So here we need a image registry.possible candidate may be Openstack galance[0]. Docker has it own image registry[1]. > Then CC can spin out Partition VM depending on policies associated with > that cartridge type. A partition will have a CC LXC agent and for the first > time it will copy relevant Cartridge images. When scaling request comes to > CC it will communicate relevant Partition’s LXC agent and agent who is > responsible for spinning up LXCs (Cartridge Processes). > In addition to that the container can be showdown if there is no request for long time and we can start the container when there is a request.This way we can improve resource re-usage.We do not need to worry about the time to the first response hence the container boot up time is very minimal if we boot up the container(boot up a image snapshot. There is a way to save image like base image +changes using union file-system) without re initialize the cartridge. > > So we need to implement this LXC agent (It should handle all LXC > management). I am looking some help from expert who in the Apache Stratos > community who may already worked on LXC. Maybe we can used existing open > source tools. Docker [1] is one I found while doing some research. > Consider warden[2] also there they have abstracted out so that they were able to build a .net warden also[3]. > > Please share your expertise on this then we can finalize how we can > implement this. We are in the process of organizing some google hangout > sessions to conduct some technical discussion of Stratos and we can discuss > this also in a hangout. > > > thanks > > [1]https://github.com/dotcloud/docker > > > -- > Lakmal Warusawithana > Software Architect; WSO2 Inc. > Mobile : +94714289692 > Blog : http://lakmalsview.blogspot.com/ > > [0]https://github.com/openstack/glance [1]https://github.com/dotcloud/docker-registry [2]https://github.com/cloudfoundry/warden/blob/master/warden/README.md [3] http://blog.ironfoundry.org/2013/07/deploy-net-apps-to-cloud-foundry-v2-with-iron-foundry/ -- Balachandiran Ajanthan Phone:+94775581497 Blog : http://ajanthan87.blogspot.com Twitter: ajanthan87 skype :bala.ajanthan gtalk :balaajanthan
