unicorn 正常的时候应该能做到无缝重启吧? 为什么我的 unicorn 每次重启时会有近半分钟无法访问,页面呈现空白的正在连接状态?
控制脚本 unicorn.sh
#!/bin/sh
case "$1" in
start)
unicorn_rails -c config/unicorn.rb -E production -D
;;
restart)
kill -USR2 $(cat /var/run/unicorn.pid)
;;
stop)
kill $(cat /var/run/unicorn.pid)
;;
*)
echo "Usage:unicorn.sh{start|restart|stop}"
;;
esac
配置 config/unicorn.rb
# Sample verbose configuration file for Unicorn (not Rack)
#
# This configuration file documents many features of Unicorn
# that may not be needed for some applications. See
# http://unicorn.bogomips.org/examples/unicorn.conf.minimal.rb
# for a much simpler configuration file.
#
# See http://unicorn.bogomips.org/Unicorn/Configurator.html for complete
# documentation.
# Use at least one worker per core if you're on a dedicated server,
# more will usually help for _short_ waits on databases/caches.
worker_processes 4
APP_PATH = "/opt/dev/xxx/"
# Since Unicorn is never exposed to outside clients, it does not need to
# run on the standard HTTP port (80), there is no reason to start Unicorn
# as root unless it's from system init scripts.
# If running the master process as root and the workers as an unprivileged
# user, do this to switch euid/egid in the workers (also chowns logs):
# user "unprivileged_user", "unprivileged_group"
# Help ensure your application will always spawn in the symlinked
# "current" directory that Capistrano sets up.
working_directory APP_PATH # available in 0.94.0+
# listen on both a Unix domain socket and a TCP port,
# we use a shorter backlog for quicker failover when busy
listen "/tmp/.sock", :backlog => 64
listen 8080, :tcp_nopush => false
# nuke workers after 30 seconds instead of 60 seconds (the default)
timeout 30
# feel free to point this anywhere accessible on the filesystem
pid "/var/run/unicorn.pid"
# By default, the Unicorn logger will write to stderr.
# Additionally, ome applications/frameworks log to stderr or stdout,
# so prevent them from going to /dev/null when daemonized here:
stderr_path "/opt/App/unicorn/logs/unicorn.stderr.log"
stdout_path "/opt/App/unicorn/logs/unicorn.stdout.log"
# combine REE with "preload_app true" for memory savings
# http://rubyenterpriseedition.com/faq.html#adapt_apps_for_cow
#preload_app true #comment this in order to restart unicorn
GC.respond_to?(:copy_on_write_friendly=) and
GC.copy_on_write_friendly = true
before_fork do |server, worker|
# the following is highly recomended for Rails + "preload_app true"
# as there's no need for the master process to hold a connection
defined?(ActiveRecord::Base) and
ActiveRecord::Base.connection.disconnect!
# The following is only recommended for memory/DB-constrained
# installations. It is not needed if your system can house
# twice as many worker_processes as you have configured.
#
# # This allows a new master process to incrementally
# # phase out the old master process with SIGTTOU to avoid a
# # thundering herd (especially in the "preload_app false" case)
# # when doing a transparent upgrade. The last worker spawned
# # will then kill off the old master process with a SIGQUIT.
# old_pid = "#{server.config[:pid]}.oldbin"
old_pid = "#{server.config[:pid]}.oldbin"
if old_pid != server.pid
begin
sig = (worker.nr + 1) >= server.worker_processes ? :QUIT : :TTOU
Process.kill(sig, File.read(old_pid).to_i)
rescue Errno::ENOENT, Errno::ESRCH
end
end
# Throttle the master from forking too quickly by sleeping. Due
# to the implementation of standard Unix signal handlers, this
# helps (but does not completely) prevent identical, repeated signals
# from being lost when the receiving process is busy.
sleep 1
end
after_fork do |server, worker|
# per-process listener ports for debugging/admin/migrations
# addr = "127.0.0.1:#{9293 + worker.nr}"
# server.listen(addr, :tries => -1, :delay => 5, :tcp_nopush => true)
# the following is *required* for Rails + "preload_app true",
defined?(ActiveRecord::Base) and
ActiveRecord::Base.establish_connection
# if preload_app is true, then you may also want to check and
# restart any other shared sockets/descriptors such as Memcached,
# and Redis. TokyoCabinet file handles are safe to reuse
# between any number of forked children (assuming your kernel
# correctly implements pread()/pwrite() system calls)
end