"Errno 5- Input/output error" while deploying app using gunicorn in a cloud VM
Hey is your gunicorn running as daemon on vm ??
If gunicorn runs in daemon then master thread sends the SIGWINCH to its child processes which is graceful termination of them. 
1.)if you are trying to daemonize gunicorn then don't go with '&' at the end of it to daemonize it. Instead use any process manager like supervisor else run it as a service.
2.)Or you can always run gunicorn inside a docker container via combination of CMD and ENTRYPPOINT.  Which in turn will not have any need of daemonizing gunicorn process. and will remain at PID1 in container. 
I guess this should solve your problem.
I have a Flask application and it is working well on my workstation. But when I am deploying my application using Gunicorn in a VM. I am getting this

Errno 5: Input/Output error

This error comes sometimes on startup of application or sometimes after that, I mean the application behaving weirdly. I googled the error but not able to find an appropriate answer that can solve my problem. 
Does anybody know the exact reason behind it?