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Michael Osipov commented on MRESOLVER-123: ------------------------------------------ [~emueller-coremedia], 1. At least the staging rules for Central running on Nexus Pro did reject SHA-2 hashes before 2.14.18. It might happen in your installation as well. Therefore, you need to check. I am just being precautious. 2. There is no release date yet since some issues are open. If you want to speed that up, pick the open issues and contribute PRs. [~rreich], I have expected this and explain why this is the case: * The lock is global (coarse) therefore every one has to wait. It is a bit of a bottleneck. * The longer the download needs the longer the lock is held by the current thread. For these two reasons I expect a rise in build times. I do expect that people use a repo manager minimizing the download time of dependencies. Our Nexus instance is 2 min physicaclly away. So you should be yours. Please try to provide build times from work with a repo manager. I think this is pretty safe to be cherry picked to 1.4.1. At the end you have to decide you want a stable, but a slower build or a fast and failing build. I would always prefer stable. The next step is to have distinct locks per group id which would reduce contention, but won't happen in this release because there are other challenges. > Concurrency issues > ------------------ > > Key: MRESOLVER-123 > URL: https://issues.apache.org/jira/browse/MRESOLVER-123 > Project: Maven Resolver > Issue Type: Bug > Components: resolver > Affects Versions: 1.4.2 > Reporter: Michael Osipov > Priority: Critical > Attachments: checksum-error-debug.log, successful-sha1-log.txt > > > This is an umbrella ticket for a long standing issue with Maven Resolver: Our > concurrency support is mediocre in a way that if two or more threads try to > download the same file and fail to queue those write actions nicely. The > problem is that The {{SyncContext}} and the its factory provided by Maven > Resolver does not employ any locking at all. As layed out in detail in > MRESOLVER-114 we need striped read write locks on artifacts and its metadata. > This issue shall track progress on it. Even Takari Concurrent Repository > extension does not help because it is only intended to synchronize concurrent > access by multple JVMs and not threads. -- This message was sent by Atlassian Jira (v8.3.4#803005)