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Links for 2015-10-29

  • Google tears Symantec a new one on its CA failure

    Symantec are getting a crash course in how to conduct an incident post-mortem to boot:

    More immediately, we are requesting of Symantec that they further update their public incident report with: A post-mortem analysis that details why they did not detect the additional certificates that we found. Details of each of the failures to uphold the relevant Baseline Requirements and EV Guidelines and what they believe the individual root cause was for each failure. We are also requesting that Symantec provide us with a detailed set of steps they will take to correct and prevent each of the identified failures, as well as a timeline for when they expect to complete such work. Symantec may consider this latter information to be confidential and so we are not requesting that this be made public.

    (tags: google symantec ev ssl certificates ca security postmortems ops)

  • Google is Maven Central’s New Best Friend

    google now mirroring Maven Central.

    (tags: google maven maven-central jars hosting java packages build)

  • Apache Kafka, Purgatory, and Hierarchical Timing Wheels

    In the new design, we use Hierarchical Timing Wheels for the timeout timer and DelayQueue of timer buckets to advance the clock on demand. Completed requests are removed from the timer queue immediately with O(1) cost. The buckets remain in the delay queue, however, the number of buckets is bounded. And, in a healthy system, most of the requests are satisfied before timeout, and many of the buckets become empty before pulled out of the delay queue. Thus, the timer should rarely have the buckets of the lower interval. The advantage of this design is that the number of requests in the timer queue is the number of pending requests exactly at any time. This allows us to estimate the number of requests need to be purged. We can avoid unnecessary purge operation of the watcher lists. As the result we achieve a higher scalability in terms of request rate with much better CPU usage.

    (tags: algorithms timers kafka scheduling timing-wheels delayqueue queueing)

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