Beefy Boxes and Bandwidth Generously Provided by pair Networks
There's more than one way to do things
 
PerlMonks  

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??

Sure, but at what point do you accept the legal responsibility for the transition with regards to your customer, and how will you handle recovery? Is it OK to replay (a series of) transitions if you keep the state in memory and write the state to disk every five minutes, while keeping a transition log? Do you want/need two-phase commit, where you send a confirmation for each processed transition?

How consistent needs the overall state of the system to be? Is it OK if all transitions for client A were processed but only the first half of the transitions for client B were processed? What if A and B own ultiple machines? What is the processing order of the transitions? Is it OK to process transitions in parallel across different threads? Is it OK to reorder transitions for a single state machine? Can a transition be cancelled or can it time out?

Most of these guarantees should be answered by a proper messaging system, like IBM MQSeries or maybe ZeroMQ nowadays, or alternatively by having all clients write directly to a database. I think you will need one, but I don't have much experience with the advantages or disadvantages of such queue systems.


In reply to Re^3: Design question: handling hundreds of state machines in a Web context by Corion
in thread Design question: handling hundreds of state machines in a Web context by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • Outside of code tags, you may need to use entities for some characters:
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others wandering the Monastery: (6)
    As of 2014-09-23 03:16 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      How do you remember the number of days in each month?











      Results (210 votes), past polls