CheckSync: Using Runtime-Integrated Checkpoints to Achieve High Availability}

TL;DR

CheckSync enables high availability for memory-managed applications by runtime-integrated checkpointing, offering smaller checkpoints and minimal performance impact compared to traditional virtual machine snapshots and live migration.

Contribution

It introduces a runtime-integrated checkpointing method for Go applications that reduces checkpoint size and performance overhead without requiring major application modifications.

Findings

CheckSync produces significantly smaller checkpoints than VM snapshots.

Running go-cache with CheckSync reduces throughput loss to 12%.

CheckSync outperforms CRIU and VM live migration in throughput preservation.

Abstract

CheckSync provides applications with high availability via runtime-integrated checkpointing. This allows CheckSync to take checkpoints of a process running in a memory-managed language (Go, for now), which can be resumed on another machine after a failure. CheckSync uses the runtime to checkpoint only the process' live memory, doing without requiring significant changes to applications. CheckSync maintains the ease of use provided by virtual machines for the applications it supports without requiring that an entire virtual machine image be snapshotted. Because CheckSync captures only the memory used by an application, it produces checkpoints that are smaller (by an order of magnitude) than virtual machine snapshots if the memory footprint of the application is relatively small compared to the state of the rest of the operating system. Additionally, when running go-cache, a popular in-memory key/value store, CheckSync reduces throughput by only 12% compared to the 78% throughput loss when using go-cache's snapshot functionality, the 45% loss when using CRIU, and the 68% loss when using virtual machine live migration.