dragonfly/doc/differences.md

Differences with Redis

String lengths, indices.

String sizes are limited to 256MB. Indices (say in GETRANGE and SETRANGE commands) should be signed 32 bit integers in range [-2147483647, 2147483648].

Expiry ranges.

Expirations are limited to 4 years. For commands with millisecond precision like PEXPIRE or PSETEX, expirations greater than 2^27ms are quietly rounded to the nearest second loosing precision of less than 0.001%.