Open Source Summit Europe 2018 - Pre-conf day

My personal notes ...

Sunday, October 21, 2018

Open Source Summit Europe 2018

Edinburgh International Conference Centre

Sunday, the real conference has not yet started. Therefore a pre-conference day. This page contains my personal notes of that day.

Control Groups

v1 vs v2

Sep 2012 cgroups v2

Cgroups v2 is still work-in-progress

V1 will be around for a long time, v1 functionality not in v2

Example pids controller (cgroups v1)

Systemd mounts the v1 controllers under subdirectories of /sys/fs/cgroup

CGroups v1 is used by Docker, LXC, Firejail, Flatpak, systemd (also knows about v2) and more.

Firejail is a sandboxing “framework”.

Flatpak, packages an app with its dependencies and makes it installable.

Show kernelthread ids

ps -L [procesid]

Slides: Introduction to cgroups

Code: Source code of the Programs in “The Linux Programming Interface” (“dist” version; unpack the tarball)

Internals of Docking Storage with Kubernetes Workloads

Dennis Chen, Arm

Storage is one of the three key elements in cloud computing, and Kubernetes is a popular container orchestration system. With more and more persistent storage volume being used in this field, it becomes increasingly challenging to deploy standalone clusters, a natural solution is to deploy a storage cluster automatically with Kubernetes primitives and make use of it like volume provisioning and attachment for the workload cluster.

Currently Kubernetes provides two frameworks to dock an external storage cluster: FlexVolume and CSI(Container Storage Interface).Consequently, there will be two parts in this session, in the first part, Dennis will dissect the internals of the two solutions: how they work, and the advantages and limitations for each one. In the second part Dennis will take the Rook project hosted by CNCF and a Ceph cluster as a specific example to discuss a practical implementation in the real world.

In-tree vs Out-of-tree

CSI, Container Storage Interface

Beta in Kubernetes v1.10

Flexvolume and CSI in in K8s

Out-of-Tree Volume plugins

in-tree CSI Volume plugin (K8s)

Flex Volume Driver Part (Rook as example)

Rook-pod connected to Ceph cluster

CSI Volume Driver Part