Inspired by this great article on Planet Cassandra. The authors report a 94% reduction in test time; I saw the same (actually greater) results when using ramdisk.

Example with docker-compose:

Setup:

cassandra-ramdisk:
  # Needs to be run in priviliged
  # mode to mount ramdisk
  privileged: true
  image: benbrostoff/cassandra-ramdisk
  # you can pass in a ramdisk size in MBs
  environment:
    - RAMDISK_SIZE=2000
  ports:
    - "9160"
    - "9042"
    - "7199"

Usage:

docker-compose up -d cassandra-ramdisk; sleep 10
docker-compose run --rm cassandra-ramdisk cqlsh cassandra-ramdisk

Connected to Test Cluster at cassandra-ramdisk:9042.
[cqlsh 5.0.1 | Cassandra 3.3 | CQL spec 3.4.0 | Native protocol v4]
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