求教redis连接Operation now in progress错误的原因

[robbinhan]

大神你好，看到你对redis研究的一些笔记，我遇到个问题想请教下。

我有一台redis的实例，近阶段经常不定时出现socket连接错误：Operation now in progress，使用的是PHP的predis库，连接是TCP连接，用的PHP内置的stream_socket_client函数。

以下是info信息，redis是跑在虚拟机上的，让运维检查过那台虚拟机上IO和CPU好像也并不高，初步怀疑是否是aof的时候阻塞导致的，请大神指教下。

redis_version:2.4.15
redis_git_sha1:00000000
redis_git_dirty:0
arch_bits:64
multiplexing_api:epoll
gcc_version:4.1.2
process_id:5630
uptime_in_seconds:41745087
uptime_in_days:483
lru_clock:500275
used_cpu_sys:3929.24
used_cpu_user:3163.36
used_cpu_sys_children:19.36
used_cpu_user_children:79.60
connected_clients:2
connected_slaves:0
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0
used_memory:363262528
used_memory_human:346.43M
used_memory_rss:465199104
used_memory_peak:363270776
used_memory_peak_human:346.44M
mem_fragmentation_ratio:1.28
mem_allocator:jemalloc-3.0.0
loading:0
aof_enabled:1
changes_since_last_save:20147336
bgsave_in_progress:0
last_save_time:1389321024
bgrewriteaof_in_progress:0
total_connections_received:25589457
total_commands_processed:49190533
expired_keys:7674576
evicted_keys:0
keyspace_hits:18294202
keyspace_misses:4860432
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:21926
vm_enabled:0
role:master
aof_current_size:880417823
aof_base_size:531405008
aof_pending_rewrite:0
aof_buffer_length:0
aof_pending_bio_fsync:0
db0:keys=947777,expires=947614

[Hailei]

这个版本有点老了，以前的版本我不怎么熟悉

[chenxuezhou]

居然是源码学习，想使用入门到精通的文章好难找