[rails] scheduler_daemon 執行出現問題.

在 scheduler_daemon.log 下發現錯誤訊息. 
# Logfile created on 2014-07-29 23:49:00 +0800 by logger.rb/31641
*** below you find the most recent exception thrown, this will be likely (but not certainly) the exception that made the application exit abnormally ***
#<NameError: uninitialized constant Rufus::EmScheduler>
*** below you find all exception objects found in memory, some of them may have been thrown in your application, others may just be in memory because they are standard exceptions ***
#<IOError: stream closed>
#<NoMemoryError: failed to allocate memory>
#<SystemStackError: stack level too deep>
#<fatal: exception reentered>
#<Errno::ENOENT: No such file or directory - /home/xxx/log/scheduler_daemon.pid>
#<NameError: uninitialized constant Rufus::Scheduler::EmScheduler>
#<NameError: uninitialized constant Rufus::EmScheduler>
#<NameError: uninitialized constant EmScheduler>
#<NameError: uninitialized constant EmScheduler>
#<NameError: uninitialized constant Rufus::EmScheduler>

主要就是要把 Gemfile.lock
rufus-scheduler (3.0.8)  改成  rufus-scheduler (2.0.24)

來源: https://github.com/ssoroka/scheduler_daemon/commit/72226e915a5b25e5695e6b7017eaefff27c90348