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QCon London 2016 Day 1

2016, conference, qcon

The kick-off day at QCon London on Monday started with Adrian Colyer summarising a number of recentpy written papers (as well as historic papers for reference) which he writes as part of his blog. He provided a a collection of references. The sslides are available speakerdeck.

What was particularly interesting about this talk is that Apple had two presentations in today’s tracks. Norman Maurer talked about Apple’s use of large-scale Netty deployments (over ½ million), and some of the contributions that he and others at Apple had made to the framework. One of them was a high-performance networking and SSL termination layer, originally ported from Twitter’s Finagle. Part of the problem is that Java’s NIO has too many synchronized locks and the Java SSL libraries generates too much garbage, which prevents maximising core usage. By providing a different SSLProvider for Netty and binding to OpenSSL/LibreSSL/BoringSSL he was able to demonstrate an increase from 10Mb/s to 60Mb/s and from a 40% utilisation of a multi-core box to 100% utilisation for a load tester. There was also a Cassandra at Apple Scale presentation, including some of the failure modes that they have seen. These have resulted in a number of fixes being applied to the codebase, including signatures for host membership and incremental rebuilding to avoid problems when incomplete data and group membership change at the same time.

There was also a blind presenter (with a really nice guide dog) who was talking about how he has been enabled by IBM’s cloud and technology in order to compete a long-distance marathon. It was a really inspiring talk and I urge you to watch the video when it’s available.

There is Java content at QCon London, but it’s certainly not the key part of the conference. The Java track had a nubmer of great presentations – Simon Ritter was talking about Modularity in Java with Jigsaw (slides); Jeurgen Hoeller was talking about Spring 5 (slides); Mark Price gave an excellent presentation on hot code is faster code (slides); and finally, but by no means least, Java 9 - The G1 GC awakens (slides).

The day finished with a great evening keynote on some of the history of Babbage, Lovelace and Turing. The talk was a duet, given by John Graham-Cunning and Sydney Paula. Hopefully the video recording and/or slides will be made available in the near future.

There are a lot of other great talks available; the schedule has a collected link of the speakers and slides (where available), and the recorded videos will be available in the future.