Busy loop on IO.select

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Hello, I noticed knife ssh (a Chef tool) sometimes pegs a core. I traced the issue back to this library, which sometimes falls into a busy IO.select loop here (via the parent's loop_forever):

net-ssh-multi/lib/net/ssh/multi/session.rb

Line 435 in f4c787e

readers, writers, = IO.select(readers, writers, nil, wait)

This happens when the readers and writers arrays are both empty.

Here are the syscalls being executed which clearly shows the issue:

[pid 25954] getpid()                    = 25954
[pid 25954] pselect6(1, [], [], NULL, {tv_sec=0, tv_nsec=0}, NULL) = 0 (Timeout)
[pid 25954] getpid()                    = 25954
[pid 25954] pselect6(1, [], [], NULL, {tv_sec=0, tv_nsec=0}, NULL) = 0 (Timeout)
[pid 25954] getpid()                    = 25954
[pid 25954] pselect6(1, [], [], NULL, {tv_sec=0, tv_nsec=0}, NULL) = 0 (Timeout)

I haven't dug into this enough to recommend a fix. Not sure if Chef is mis-using this library or if it's purely a library bug, but either way it seems the library shouldn't get into this state.