move_redis_list.py

import redis

# Number of records to move at once
N = 10000
# DB number and key
DB = 3
KEY = 'deletion_notices'


source = redis.StrictRedis('<source host>', db=DB)
dest = redis.StrictRedis('<dest host>', db=DB)

source.ping()
dest.ping()


records_moved = 0
records_to_move = source.llen(KEY)

print("Moving %i records..." % (records_to_move // 1000))

while True:
    chunk = source.lrange(KEY, 0, N-1)
    if not chunk:
        break
    dest.rpush(KEY, *chunk)
    source.ltrim(KEY, N, -1)
    records_moved += len(chunk)
    print('{}k records moved, {}k records to go'.format(
        records_moved // 1000, (records_to_move - records_moved)  // 1000))

print("Done!")