[sas@nnsasmtp01 admin]$ for x in $(seq 1 50); do sleep 10 & done
-bash: fork: retry: Resource temporarily unavailable
[1] 3223
-bash: fork: retry: Resource temporarily unavailable
[2] 3225
[3] 3226
[4] 3227
[5] 3228
[6] 3229
[7] 3230
[8] 3231
[9] 3232
[10] 3233
[11] 3234
[12] 3235
-bash: fork: retry: Resource temporarily unavailable
[13] 3236
-bash: fork: retry: Resource temporarily unavailable
-bash: fork: retry: Resource temporarily unavailable
-bash: fork: retry: Resource temporarily unavailable
-bash: fork: retry: Resource temporarily unavailable
-bash: fork: Resource temporarily unavailable
[1]   Done                    sleep 10
[2]   Done                    sleep 10
[3]   Done                    sleep 10
[4]   Done                    sleep 10
[5]   Done                    sleep 10
[6]   Done                    sleep 10
[7]   Done                    sleep 10
[8]   Done                    sleep 10
[9]   Done                    sleep 10
[10]   Done                    sleep 10
[11]   Done                    sleep 10
[12]-  Done                    sleep 10
[13]+  Done                    sleep 10