Unicorn restart error Failed to create timer thread (errno: 11)

I am trying to restart unicorn service on my rails app but getting this error in logs. Please help.

I, [2018-03-09T09:27:10.028799 #16454]  INFO -- : listening on addr=/tmp/unicorn.sanddollar.sock fd=10
I, [2018-03-09T09:27:10.029139 #16454]  INFO -- : worker=0 spawning...
I, [2018-03-09T09:27:10.031123 #16454]  INFO -- : worker=1 spawning...
I, [2018-03-09T09:27:10.031790 #16457]  INFO -- : worker=0 spawned pid=16457
I, [2018-03-09T09:27:10.031984 #16457]  INFO -- : Refreshing Gem list
I, [2018-03-09T09:27:10.032334 #16454]  INFO -- : worker=2 spawning...
[FATAL] Failed to create timer thread (errno: 11)
I, [2018-03-09T09:27:10.036780 #16460]  INFO -- : worker=1 spawned pid=16460
I, [2018-03-09T09:27:10.037023 #16460]  INFO -- : Refreshing Gem list
[FATAL] Failed to create timer thread (errno: 11)
I, [2018-03-09T09:27:30.690995 #16460]  INFO -- : worker=1 ready
I, [2018-03-09T09:27:30.852442 #16457]  INFO -- : worker=0 ready