EM.epoll
EM.run do
trap("TERM") { stop(config['pid']) }
trap("INT") { stop(config['pid']) }
Router.config(config)
Router.log.info "Starting VCAP Router (#{Router.version})"
Router.log.info "Listening on: #{inet}:#{port}" if inet && port
Router.inet = inet || VCAP.local_ip(config['local_route'])
Router.port = port
# If the sock paramater is set, this will override the inet/port
# for unix domain sockets
if fn = config['sock']
File.unlink(fn) if File.exists?(fn)
Router.log.info "Listening on unix domain socket: '#{fn}'"
end
# Hack for running on BVTs on Macs which default to 256 FDs per process
if RUBY_PLATFORM =~ /darwin/
begin
Process.setrlimit(Process::RLIMIT_NOFILE, 4096)
rescue => e
Router.log.info "Failed to modify the socket limit: #{e}"
end
end
EM.set_descriptor_table_size(32768) # Requires Root privileges
Router.log.info "Socket Limit:#{EM.set_descriptor_table_size}"
create_pid_file(config['pid'])
NATS.on_error do |e|
if e.kind_of? NATS::ConnectError
Router.log.error("EXITING! NATS connection failed: #{e}")
exit!
else
Router.log.error("NATS problem, #{e}")
end
end
EM.error_handler do |e|
Router.log.error "Eventmachine problem, #{e}"
Router.log.error("#{e.backtrace.join("\n")}")
end
begin
# TCP/IP Socket
Router.server = EM.start_server(inet, port, ClientConnection, false) if inet && port
Router.local_server = EM.start_server(fn, nil, ClientConnection, true) if fn
rescue => e
Router.log.fatal "Problem starting server, #{e}"
exit
end
求教 1,EM.epoll 是什么意思？网上看了似懂非懂的
2, trap("TERM") { stop(config['pid']) } trap("INT") { stop(config['pid']) } 这是什么意思，谢谢
这是用 EventMachine 来作事情呀，你首先就应该看 EventMachine 的文档
- EM 是 EventMachina 的简写，EM 跟 EventMachina 一样。EM.epoll 参见这里： http://eventmachine.rubyforge.org/docs/EPOLL.html
- trap("TERM") 的意思是接收来自系统的“TERM”信号，然后执行 block 中的代码
- trap("INT") 跟上面同理。
给你建议
- 你的主题帖子要改成“都 EventMachine 的代码遇到的问题，求教”
- 你的问题需要编号，然后才能让大家针对具体编号的问题跟你讨论。
kehao
#2
2012年02月21日
第 2 个问题 kill -Signal pid signal 是发送给进程的信号，TERM(或数字 9）表示“无条件终止” 信号 INT(或数字 2)，就是 ctrl+c
#3 楼 @kehao 讲 epoll 的文档都喜欢用难懂的语言解释这个东西本身。 简单的说就是帮助你解决大并发连接的问题，比如这个： http://www.kegel.com/c10k.html
kehao
#7
2012年02月21日
#6 楼 @clc3123 这个是 VMware's Cloud Application Platform 的源代码，我是拉下来学习学习的 https://github.com/derekcollison/vcap
第 2 个问题 Name Num Action Description INT 2 exit KILL 9 exit cannot be blocked TERM 15 exit USR1 exit USR2 exit
9) SIGKILL 用来立即结束程序的运行。本信号不能被阻塞，处理和忽略. 15) SIGTERM 程序结束 (terminate) 信号，与 SIGKILL 不同的是该信号可以被阻塞和 处理。通常用来要求程序自己正常退出。shell 命令 kill 缺省产生这个信号. 12) SIGUSR2 留给用户使用
require 'eventmachine'
module EchoServer
def post_init
puts "-- init"
end
def receive_data data
send_data "-- you sent: #{data}"
close_connection if data =~ /quit/i
end
def unbind
puts "-- disconnected"
end
end
EventMachine::run {
trap("TERM") { puts "==>TERM" }
trap("USR2") { puts "==>USR2" }
trap("KILL") { puts "==>KILL" }
trap("INT") { puts "==>INT"}
EventMachine::start_server "127.0.0.1", 8081, EchoServer
}
kill -USR2 13059 ==>USR2
kehao
#10
2012年02月21日
#9 楼 @calebx 感谢纠正 想起 unicorn 的重启好像用的 run "kill -USR2 `cat #{deploy_to}/current/tmp/pids/unicorn.pid`" 看了下 unicorn 源码：
＃lib/unicorn/http_server.rb
case SIG_QUEUE.shift
when :QUIT # graceful shutdown
break
when :TERM, :INT # immediate shutdown
stop(false)
break
when :USR1 # rotate logs
logger.info "master reopening logs..."
Unicorn::Util.reopen_logs
logger.info "master done reopening logs"
kill_each_worker(:USR1)
when :USR2 # exec binary, stay alive in case something went wrong
reexec
#.....
end
def reexec
#....
self.reexec_pid = fork do
listener_fds = Hash[LISTENERS.map do |sock|
# IO#close_on_exec= will be available on any future version of
# Ruby that sets FD_CLOEXEC by default on new file descriptors
# ref: http://redmine.ruby-lang.org/issues/5041
sock.close_on_exec = false if sock.respond_to?(:close_on_exec=)
[ sock.fileno, sock ]
end]
ENV['UNICORN_FD'] = listener_fds.keys.join(',')
Dir.chdir(START_CTX[:cwd])
cmd = [ START_CTX[0] ].concat(START_CTX[:argv])
# avoid leaking FDs we don't know about, but let before_exec
# unset FD_CLOEXEC, if anything else in the app eventually
# relies on FD inheritence.
(3..1024).each do |io|
next if listener_fds.include?(io)
io = IO.for_fd(io) rescue next
IO_PURGATORY << io
io.fcntl(Fcntl::F_SETFD, Fcntl::FD_CLOEXEC)
end
# exec(command, hash) works in at least 1.9.1+, but will only be
# required in 1.9.4/2.0.0 at earliest.
cmd << listener_fds if RUBY_VERSION >= "1.9.1"
logger.info "executing #{cmd.inspect} (in #{Dir.pwd})"
before_exec.call(self)
exec(*cmd)
end
proc_name 'master (old)'
#...
end
before_fork do |server, worker|
old_pid = "#{Rails.root}/tmp/pids/unicorn.pid.oldbin"
if File.exists?(old_pid) && server.pid != old_pid
begin
Process.kill("QUIT", File.read(old_pid).to_i)
rescue Errno::ENOENT, Errno::ESRCH
puts "Send 'QUIT' signal to unicorn error!"
end
end
end
