nutcracker(8) Fast, light-weight proxy for memcached and Redis


nutcracker [options]


nutcracker, also known as twemproxy (pronounced "two-em-proxy"), is a fast and lightweight proxy for the memcached and Redis protocols.

It was primarily built to reduce the connection count on backend caching servers, but it has a number of features, such as:

  • Maintains persistent server connections to backend servers.
  • Enables pipelining of requests and responses.
  • Supports multiple server pools simultaneously.
  • Shard data automatically across multiple servers.
  • Supports multiple hashing modes including consistent hashing and distribution.
  • High-availability by disabling nodes on failures.
  • Observability through stats exposed on stats monitoring port.


-h, --help
Show usage information and exit.
-V, --version
Show version and exit.
-t, --test-conf
Test configuration for syntax errors and exit.
-D, --describe-stats
Print stats description and exit.
-v, --verbosity=N
Set logging level to N. (default: 5, min: 0, max: 11)
-o, --output=filename
Set logging file to filename.
-c, --conf-file=filename
Set configuration file to filename.
-s, --stats-port=port
Set stats monitoring port to port. (default: 22222)
-a, --stats-addr=address
Set stats monitoring IP to address. (default:
-i, --stats-interval=interval
Set stats aggregation interval in msec to interval. (default: 30000 msec)
-m, --mbuf-size=size
Set size of mbuf chunk in bytes to size. (default: 16384 bytes)
-d, --daemonize
Run as a daemon.
-p, --pid-file=filename
Set pid file to filename.


nutcracker was written by Twitter, Inc.