1 / 7

Efficiently Managing System Upgrades in Distributed Environment

Learn how to automatically upgrade large, long-lived distributed systems without disrupting service, using strategies like scheduling, simulation, and transformation of persistent state. The upgrade infrastructure supports seamless propagation and installation of new code versions.

ldemers
Download Presentation

Efficiently Managing System Upgrades in Distributed Environment

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Upgrading Distributed Systemsis not rsync Sameer Ajmani Barbara Liskov Liuba Shrira MIT Lab for Computer Science

  2. Large, Long-Lived Distributed SystemsNeed Automatic Upgrades • e.g., CDNs, peer-to-peer nets, sensor nets • Software must change over time • No direct operator access • Upgrades must propagate automatically • Upgrades must avoid disrupting service

  3. A System Upgrade Version 1 Version 2 • Each node runs at a particular version • New version information propagates to nodes • A node upgrades by shutting down, installing new code, transforming its persistent state, and restarting • These systems are robust, so they tolerate node restarts

  4. Upgrades Can Disrupt Service Version 1 Version 2 • A node cannot service requests while upgrading • May need to delay a node upgrade • To avoid causing too many simultaneous failures • To test an upgrade on a few nodes • Implies mixed mode operation

  5. Mixed Mode Operation Version 2 Version 1

  6. Simulation Enables Interoperation Version 1 Node Version 2 • Nodes label outgoing calls with their version • Nodes dispatch incoming calls to simulation objects • Installing a simulation object is much faster than upgrading • Both upgraded and non-upgraded nodes use simulation • Imperfect simulation may degrade service

  7. Summary • Upgrades require scheduling and simulation • Other issues (covered in the paper) • Transforms for persistent state • Correctness of transforms and simulation • An upgrade infrastructure that supports upgrade propagation, scheduling, code installation, transforms, and simulation

More Related