Re:Containers, Not Virtual Machines, Are the Future Cloud
by gundy on Tuesday June 18, 2013 @02:30PM
(#5901070)
They are not really efficient. All they do is add an extra layer of security so you can encapsulate that specific process in a chroot with its own networking stack. Other than that the CPU is still fairshared and the memory still has the same limits as if you ran it without the container. It adds nothing but security.
Re:Containers, Not Virtual Machines, Are the Future Cloud
by wmf on Tuesday June 18, 2013 @02:55PM
(#5901228)
In the cloud, KVM/Xen overhead is considered the baseline so containers are definitely more efficient by comparison.
Re:Containers, Not Virtual Machines, Are the Future Cloud
by alinspired on Tuesday June 18, 2013 @03:14PM
(#5901337)
There are container technologies (openvz, LXC) that offer lot more than "fairshared" to manage resources between containers. Plus the efficiencies of lower "virtualization overhead", because you don't have full OS in containers compared to VMs (consider full VM kernel, VM HW drivers, etc)
Another benefit for PaaS/SaaS is that you don't necessarily sell RAM or DISK, you sell an application/service and thus can take FULL advantage of containers, like: - more efficient resources sharing(on host) - dynamic resources re-balancing - quicker start/stop/etc
Containers can be used to offer IaaS, but as was already mentioned in this thread, a few edge cases (custom kernel or kernel module, any filesystems support, any firewall support) prevent it due to support/operations overhead.