cleanup graceful shutdown handling

Using a 10ms tick was too little, use 100ms instead to avoid
burning CPU.  Ideally, we would not tick at all during shutdown
(we're normally tickless); but the common case could be
slightly more expensive; and shutdowns are rare (I hope).

Then, change our process title to indicate we're shutting down,
and finally, cut down on repeated log spew during shutdown and
only log dropping changes.

This mean we could potentially take 90ms longer to notice when
we can do a graceful shutdown, but oh well...

While we're at it, add a test to ensure graceful shutdowns
work as intended with multiple processes.

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/yahns/server_mp.rb b/lib/yahns/server_mp.rb
index fa12a0c..c9cd207 100644
--- a/lib/yahns/server_mp.rb
+++ b/lib/yahns/server_mp.rb
@@ -159,7 +159,7 @@ module Yahns::ServerMP # :nodoc:
   def mp_sig_handle(watch, alive)
     # not performance critical
     watch.delete_if { |io| io.to_io.closed? }
-    if r = IO.select(watch, nil, nil, alive ? nil : 0.01)
+    if r = IO.select(watch, nil, nil, alive ? nil : 0.1)
       r[0].each(&:yahns_step)
     end
     case @sig_queue.shift