How to optimize JVM to process 175k transactions per sec?

Sanhong Li, JVM at Alibaba talks about how his company managed to process giant transactions amount at the world's largest online shopping event
04 August 2017   787

Alibaba Group is a Chinese public company working in the field of Internet commerce, the owner of B2B web portal Alibaba.com. This is one the world-largest internet companies. 

Company manages:

  • Alibaba.com 
  • Alibaba Pictures 
  • AliExpress.com 
  • Taobao.com 
  • Alipay 
  • 1688.com
  • Tmall.com
  • Juhuasuan
  • eTao
  • Alibaba Cloud Computing
  • China Yahoo!

On 11.11.16, Alibaba beat it own record - company was able to process 175 000 transactions per second. A lot of Alibaba’s e-Commerce app use Java. To cater for the specific needs to run these applications, team identified the requirements and optimized these features on the customized version of HotSpot (OpenJDK based). 

At this report, Sanhong talked about: 

  • how they characterize workloads to identify specific needs;
  • optimization and customizing HotSpot for Java apps.

Alibaba's team identified three specific features useful for their needs:

  • put multiple containers into one JVM instance, which allows to deploy many small Java applications in large scale, across data centers,
  • use coroutines (from Da Vinci Machine project) to reduce context switches,
  • implement quick Java warmup to obviate the need for "warming-up" occurred in initialization phase of the eCommerce applications

What is Web3j?

Small review of lightweight Java and Android library for integration with Ethereum clients
15 December 2017   817

What is webj3?

web3j is a lightweight, highly modular, reactive, type safe Java and Android library for working with Smart Contracts and integrating with clients (nodes) on the Ethereum network:

web3j architecture
Web3j Architecture

This allows you to work with the Ethereum blockchain, without the additional overhead of having to write your own integration code for the platform.

According to the developers, these are the features:

  • Complete implementation of Ethereum's JSON-RPC client API over HTTP and IPC
  • Ethereum wallet support
  • Auto-generation of Java smart contract wrappers to create, deploy, transact with and call smart contracts from native Java code (Solidity and Truffle definition formats supported)
  • Reactive-functional API for working with filters
  • Ethereum Name Service (ENS) support
  • Support for Parity's Personal, and Geth's Personal client APIs
  • Support for Infura, so you don't have to run an Ethereum client yourself
  • Comprehensive integration tests demonstrating a number of the above scenarios
  • Command line tools
  • Android compatible
  • Support for JP Morgan's Quorum via web3j-quorum

It has five runtime dependencies:

  • RxJava for its reactive-functional API
  • OKHttp for HTTP connections
  • Jackson Core for fast JSON serialisation/deserialisation
  • Bouncy Castle (Spongy Castle on Android) for crypto
  • Jnr-unixsocket for *nix IPC (not available on Android)

It also uses JavaPoet for generating smart contract wrappers.

Lear more at GitHub.