I have seen in various threads on the list that 3.0.x is probably best for prod. Just wondering though if there is anything in particular in 3.7 to be weary of.
I need to check with one of our QA engineers to get specifics on the storage. Here is what I do know. We have a blade center running lots of virtual machines for various testing. Some of those vm's are running Cassandra and the Java web apps I previously mentioned via docker containers. The storage is shared. Beyond that I don't have any more specific details at the moment. I can also tell you that the storage can be quite slow. I have come across different threads that talk to one degree or another about the flush queue getting full. I have been looking at the code in ColumnFamilyStore.java. Is perDiskFlushExecutors the thread pool I should be interested in? It uses an unbounded queue, so I am not really sure what it means for it to get full. Is there anything I can check or look for to see if writes are getting blocked? On Tue, Sep 20, 2016 at 8:41 PM, Jonathan Haddad <j...@jonhaddad.com> wrote: > If you haven't yet deployed to prod I strongly recommend *not* using 3.7. > > What network storage are you using? Outside of a handful of highly > experienced experts using EBS in very specific ways, it usually ends in > failure. > > On Tue, Sep 20, 2016 at 3:30 PM John Sanda <john.sa...@gmail.com> wrote: > >> I am deploying multiple Java web apps that connect to a Cassandra 3.7 >> instance. Each app creates its own schema at start up. One of the schema >> changes involves dropping a table. I am seeing frequent client-side >> timeouts reported by the DataStax driver after the DROP TABLE statement is >> executed. I don't see this behavior in all environments. I do see it >> consistently in a QA environment in which Cassandra is running in docker >> with network storage, so writes are pretty slow from the get go. In my logs >> I see a lot of tables getting flushed, which I guess are all of the dirty >> column families in the respective commit log segment. Then I seen a whole >> bunch of flushes getting queued up. Can I reach a point in which too many >> table flushes get queued such that writes would be blocked? >> >> >> -- >> >> - John >> > -- - John
