Swift hardcode MAX_PROC=8192 and some daemons unable to fork processes

[Charles Hsu]

It's hardcode to 8192, it might hit `Error: [Errno 11] Resource temporarily unavailable` when swift daemons try to fork more processes.

https://github.com/openstack/swift/blob/master/swift/common/manager.py#L58

### Exception in object-updater

```
Feb 20 23:48:48 SWIFT-NODE object-updater: UNCAUGHT EXCEPTION#012Traceback (most recent call last):#012 File "/opt/ss/bin/swift-object-updater", line 23, in <module>#012 run_daemon(ObjectUpdater, conf_file, **options)#012 File "/usr/lib/pymodules/python2.7/swift/common/daemon.py", line 117, in run_daemon#012 klass(conf).run(once=once, **kwargs)#012 File "/usr/lib/pymodules/python2.7/swift/common/daemon.py", line 58, in run#012 self.run_forever(**kwargs)#012 File "/usr/lib/pymodules/python2.7/swift/obj/updater.py", line 92, in run_forever#012 pid = os.fork()#012OSError: [Errno 11] Resource temporarily unavailable
```

[Matthew Oliver (matt-0)]

It might hit. Is this something you've faced? I.e have you run out of MAX_PROCS?

If so, wow that's alot of processes you have running, it must be some beefy server. If it is a stumbling block we could go and raise it.

[clayg (clay-gerrard)]

This might be a dupe of https://bugs.launchpad.net/swift/+bug/1554233 (fixed in swift > 2.15)