Hi Folks,
I am glad to announce 1.0 release of BackgrounDRb.
This would be a major release since 0.2 release of BackgrounDRb.
Here is a brief summary of changes:
- BackgrounDRb is DRb no longer. It makes use of EventDriven network programming library packet ( http://packet.googlecode.com ).
- Since we moved to packet, many nasty thread issues, result hash corruption issues are totally gone. Lots of work has went in making scheduler rock solid stable.
- Each worker, still runs in its own process, but each worker has a event loop of its own and all the events are triggered by the internal reactor loop. In a nutshell, you are not encouraged to use threads in your workers now. All the workers are already concurrent, but you are encouraged to use co-operative multitasking, rather than pre-emptive. A simple example is,
For implement something like progress bar in old version of bdrb, you would: - start your processing a thread (so as your worker can receive further request from rails ) and have a instance variable ( protected by mutex ) which is updated on progress and can be send to rails.
- With new backgroundrb, progress bar would be: process your damn request and just use register_status() to register status of your worker. Just because you are doing some processing won't mean that your worker will block. It can still receive requests from rails.
- Now, you can schedule multiple methods with their own triggers.
> :schedules: > :foo_worker: > :foobar: > :trigger_args: */5 * * * * * * > :data: Hello World > :barbar: > :trigger_args: */10 * * * * * *
- Inside each worker, you can start tcp server or connect to a external server. Two important methods available in all workers are:
start_server("localhost",port,ModuleName) connect("localhost",port,ModuleName)
Connected client or outgoing connection would be integrated with Event Loop and you can process requests from these guys asynchronously. This mouse trap can allow you to build truly distributed workers across your network.
- Each worker comes with a "thread_pool" object, which can be used to run tasks concurrently. For example:
thread_pool.defer(url) { |url| scrap_wiki_content(url) }
- Each worker has access to method "register_status" which can be used to update status of worker or store results. Results of a worker can be retrieved even after a worker has died.
By default the results would be saved in master process memory, but you can configure BackgrounDRb to store these results in a memcache server or a cluster using following option in configuration file:
# backgroundrb.yml
> :backgroundrb: > :port: 11006 > :ip: 0.0.0.0 > :log: foreground > :result_storage: > :memcache: "10.10.10.2:11211,10.10.10.6:11211"
- Relevant URLs: ** Home Page: http://backgroundrb.rubyforge.org ** SVN : http://svn.devjavu.com/backgroundrb/trunk ** Bug Reports/Ticks: http://backgroundrb.devjavu.com/report
- Credits : ** Ezra Zygmuntowicz,skaar for taking BackgrounDRb so far. ** Kevin for helping out with OSX issues. ** Andy for patches and initial testing. ** Paul for patching up README. ** Other initial users. ** Matz, Francis for general inspiration.