[GitHub] [hbase] joshelser commented on pull request #3488: HBASE-25393 Support split and merge region with direct insert into CF…

[GitBox <gi...@apache.org>]

joshelser commented on pull request #3488:
URL: https://github.com/apache/hbase/pull/3488#issuecomment-884452513


   > I guess why we create it in tmp directory first is because the CatalogJanitor? Not sure. But theoretically, since we do not need to scan the filesystem to get all the regions for a table when opening it, I do not think we need to introduce a Strategy to handle both cases, just change the code to write it to the final place. This could be done on master and branch-2.
   
   > I guess hbck recovery could be a problem for the default tracking, if the resulting merging/splitting region dir got already created in the FS, fails before completing the operation then vanishes from meta
   
   That's a fun thought. Things like rebuilding meta from the filesystem suddenly become dubious. I think we also know that building and HBCK which is capable of identifying a "split-in-progress" is hard. Like Duo say, we can put the Region in the "correct" place and it will just be used once meta is updated.
   
   What if we had some special marker in the Region which we cleaned up after it was opened the first time? HBCK could look for that marker and know that if we find a Region on the FS with this marker that isn't in meta, we should be able to just ignore/delete it (as a split/merge which was in-flight).


-- 
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.

To unsubscribe, e-mail: issues-unsubscribe@hbase.apache.org

For queries about this service, please contact Infrastructure at:
users@infra.apache.org