LantaoJin commented on pull request #28938: URL: https://github.com/apache/spark/pull/28938#issuecomment-650868622
> Hi, @LantaoJin . Since this PR aims to use multiple locks instead of a global one, could you add some explanation briefly about how this PR is deadlock-free? Thanks. Sure. The multiple read-write reentrant locks are divided by different databases. Only operations applied in the same database name could share a same lock. I checked all operations, there is no one operation and its callers need two write locks. Since it's a reentrant lock, it's ok that the method `renamePartitions` which calls `alterPartitions` will re-enter the same write lock. Besides, this patch has been online for a long time in our production (over 1 year moved object lock to read-write lock and over 5 months separated to multiple locks per database). ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
