From 5bc5f36b5e5aef6340d94f8809122ac81fe466a2 Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Mon, 27 Mar 2017 20:59:54 +0000 Subject: USR2 upgrades may use Process.spawn for vfork Remove false statements about close-on-exec being cleared in the parent process (verified via strace) and refactor the code to take full advantage of options for Process.spawn and Process.exec. This avoids unnecessary CoW traffic for the common case where before_exec is unset. --- lib/yahns/server.rb | 33 ++++++++++++++++----------------- 1 file changed, 16 insertions(+), 17 deletions(-) diff --git a/lib/yahns/server.rb b/lib/yahns/server.rb index 00e5f15..5411c48 100644 --- a/lib/yahns/server.rb +++ b/lib/yahns/server.rb @@ -237,24 +237,23 @@ class Yahns::Server # :nodoc: end end - # We cannot use Process.spawn here because of redirects + close-on-exec - # We must keep close_on_exec=true in the parent process and only set - # close_on_exec=false in the child. There must be no opportunity - # for the user app to ever get a listen socket with close_on_exec=false - @reexec_pid = fork do - redirects = {} - @listeners.each do |sock| - sock.close_on_exec = false - redirects[sock.fileno] = sock + opt = {} + @listeners.each { |sock| opt[sock.fileno] = sock } + env = ENV.to_hash + env['YAHNS_FD'] = opt.keys.join(',') + opt[:close_others] = true + cmd = [ Yahns::START[0] ].concat(Yahns::START[:argv]) + dir = @config.value(:working_directory) || Yahns::START[:cwd] + @logger.info "spawning #{cmd.inspect} (in #{dir})" + @reexec_pid = if @before_exec + fork do + Dir.chdir(dir) + @before_exec.call(cmd) + exec(env, *cmd, opt) end - ENV['YAHNS_FD'] = redirects.keys.join(',') - redirects[:close_others] = true - Dir.chdir(@config.value(:working_directory) || Yahns::START[:cwd]) - cmd = [ Yahns::START[0] ].concat(Yahns::START[:argv]) - @logger.info "executing #{cmd.inspect} (in #{Dir.pwd})" - @before_exec.call(cmd) if @before_exec - cmd << redirects - exec(*cmd) + else + opt[:chdir] = dir + spawn(env, *cmd, opt) end end -- cgit v1.2.3-24-ge0c7