Platform: Win 10 Version: 3.2.100 64 Bit

[2116] 07 Jun 10:59:08.603 * Redis 3.2.100 (00000000/0) 64 bit, standalone mode, port 6379, pid 2116 ready to start.
[2116] 07 Jun 10:59:08.620 # Server started, Redis version 3.2.100
[2116] 07 Jun 10:59:10.379 * DB loaded from disk: 1.759 seconds
[2116] 07 Jun 10:59:10.379 * The server is now ready to accept connections on port 6379
[2116] 07 Jun 11:14:09.320 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:14:09.568 * Background saving started by pid 3624
[2116] 07 Jun 11:14:09.671 # fork operation failed
[2116] 07 Jun 11:14:11.426 # Background saving terminated by signal 1
[2116] 07 Jun 11:14:25.705 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:14:25.758 * Background saving started by pid 4316
[2116] 07 Jun 11:14:39.057 # fork operation failed
[2116] 07 Jun 11:14:54.039 # Background saving terminated by signal 1
[2116] 07 Jun 11:14:54.162 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:14:54.298 * Background saving started by pid 3324
[2116] 07 Jun 11:14:54.399 # fork operation failed
[2116] 07 Jun 11:15:08.809 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:11.942 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:12.024 * Background saving started by pid 5064
[2116] 07 Jun 11:15:12.225 # fork operation failed
[2116] 07 Jun 11:15:16.691 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:17.094 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:17.105 * Background saving started by pid 5096
[2116] 07 Jun 11:15:17.206 # fork operation failed
[2116] 07 Jun 11:15:22.391 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:23.093 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:23.104 * Background saving started by pid 1372
[2116] 07 Jun 11:15:23.305 # fork operation failed
[2116] 07 Jun 11:15:28.132 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:29.035 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:29.045 * Background saving started by pid 5392
[2116] 07 Jun 11:15:29.146 # fork operation failed
[2116] 07 Jun 11:15:33.971 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:35.073 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:35.083 * Background saving started by pid 560
[2116] 07 Jun 11:15:35.184 # fork operation failed
[2116] 07 Jun 11:15:39.975 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:41.077 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:41.087 * Background saving started by pid 624
[2116] 07 Jun 11:15:41.188 # fork operation failed
[2116] 07 Jun 11:15:46.012 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:47.014 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:47.024 * Background saving started by pid 700
[2116] 07 Jun 11:15:47.125 # fork operation failed
[2116] 07 Jun 11:15:51.979 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:53.081 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:53.091 * Background saving started by pid 5148
[2116] 07 Jun 11:15:53.191 # fork operation failed
[2116] 07 Jun 11:15:58.015 # Background saving terminated by signal 1
[2116] 07 Jun 11:15:59.017 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:15:59.027 * Background saving started by pid 6548
[2116] 07 Jun 11:15:59.127 # fork operation failed
[2116] 07 Jun 11:16:03.941 # Background saving terminated by signal 1
[2116] 07 Jun 11:16:05.043 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:05.054 # BeginForkOperation: system error caught. error code=0x000005af, message=Problem creating slave process: unknown error

[2116] 07 Jun 11:16:05.055 # Can't save in background: fork: No such file or directory
[2116] 07 Jun 11:16:11.072 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:11.088 # BeginForkOperation: system error caught. error code=0x000005af, message=Problem creating slave process: unknown error

[2116] 07 Jun 11:16:11.090 # Can't save in background: fork: No such file or directory
[2116] 07 Jun 11:16:17.093 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:17.103 * Background saving started by pid 2768
[2116] 07 Jun 11:16:17.204 # fork operation failed
[2116] 07 Jun 11:16:21.061 # Background saving terminated by signal 1
[2116] 07 Jun 11:16:23.064 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:23.074 * Background saving started by pid 4420
[2116] 07 Jun 11:16:23.175 # fork operation failed
[2116] 07 Jun 11:16:26.581 # Background saving terminated by signal 1
[2116] 07 Jun 11:16:29.084 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:29.094 * Background saving started by pid 4220
[2116] 07 Jun 11:16:29.194 # fork operation failed
[2116] 07 Jun 11:16:32.695 # Background saving terminated by signal 1
[2116] 07 Jun 11:16:35.098 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:35.108 * Background saving started by pid 5808
[2116] 07 Jun 11:16:35.209 # fork operation failed
[2116] 07 Jun 11:16:38.896 # Background saving terminated by signal 1
[2116] 07 Jun 11:16:41.099 * 1 changes in 900 seconds. Saving...
[2116] 07 Jun 11:16:41.109 * Background saving started by pid 7040
[2116] 07 Jun 11:16:41.209 # fork operation failed

Comment From: zh1an

Why happend to this, and how to avoid it?