Michael Harris created HADOOP-12412: ---------------------------------------
Summary: Concurrency in FileSystem$Cache is very broken Key: HADOOP-12412 URL: https://issues.apache.org/jira/browse/HADOOP-12412 Project: Hadoop Common Issue Type: Bug Components: fs Affects Versions: 2.7.0 Reporter: Michael Harris Assignee: Michael Harris Priority: Critical The FileSystem cache uses a mild amount of concurrency to protect the cache itself, but does nothing to prevent multiple of the same filesystem from being constructed and initialized simultaneously. At best, this leads to potentially expensive wasted work. At worst, as is the case for Spark, it can lead to deadlocks/livelocks, especially when the same configuration object is passed into both calls. This should be refactored to use a results cache approach (reference Java Concurrency in Practice chapter 5 section 6 for an example of how to do this correctly), which will be both higher-performance and safer. -- This message was sent by Atlassian JIRA (v6.3.4#6332)