在redis命令行中输入info:

redis 127.0.0.1:6379> info

下面返回的结果中，used_memory即为redis占用内存的情况。
redis_version:2.4.5
redis_git_sha1:00000000
redis_git_dirty:0
arch_bits:64
multiplexing_api:epoll
process_id:3607
uptime_in_seconds:1358916
uptime_in_days:15
lru_clock:846306
used_cpu_sys:81080.27
used_cpu_user:39066.05
used_cpu_sys_children:39375.31
used_cpu_user_children:932985.56
connected_clients:133
connected_slaves:0
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0
used_memory:23513760320
used_memory_human:21.90G
used_memory_rss:19985154048
used_memory_peak:23518773032
used_memory_peak_human:21.90G
mem_fragmentation_ratio:0.85
mem_allocator:jemalloc-2.2.5
loading:0
aof_enabled:0
changes_since_last_save:39637
bgsave_in_progress:1
last_save_time:1371611772
bgrewriteaof_in_progress:0
total_connections_received:85398032
total_commands_processed:3428552264
expired_keys:0
evicted_keys:0
keyspace_hits:2367826707
keyspace_misses:1265424746
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:638143
vm_enabled:0
role:master
db0:keys=30822722,expires=0