Insert of large JSON data for Cassandra driver very slow

Thanks for posting that information. I would recommend that you increase the amount of memory assigned by editing line 35 in yb-docker-ctl from:

   MEM_LIMIT_BYTES = 1024 * 1024 * 1024

to

   MEM_LIMIT_BYTES = 8 * 1024 * 1024 * 1024

This will increase the sizes of other tunables and should help improve performance.
Hope this helps.
–Alan