My thinking is that it waits till the next chunk is published. That shouldn't lead to too much lag in the system but it pre-supposes that processes transmit state even in the absence of change. That isn't a stretch since many sensors publish regular updates even in the absence of change.
On Monday, February 18, 2013 2:49:03 PM UTC-5, Michael Schoonmaker wrote: > > Mike, > When it comes to "taking the output" of sensors or other processes, > what happens when a new process is added to the mesh? Should it be > able to ask for the current sensor state, or simply sit idle until the > next chunk of output is published to the mesh? > > -Schoon > > On Mon, Feb 18, 2013 at 10:39 AM, Angel Java Lopez > <ajlop...@gmail.com <javascript:>> wrote: > > Hi people! > > > > Mike, I guess the main approaches to take are: > > > > - A distributed actor model > > - A service bus > > > > For the second option (started some month ago, but revamped inspired by > your > > link about hook.io), I wrote: > > https://github.com/ajlopez/SimpleBus > > See some distributed tests > > https://github.com/ajlopez/SimpleBus/blob/master/test/client.js > > > > I have code for the first option, too, but I guess the second is the > > simplest to follow now, baby steps. My solution is a "pet project" but > it > > could serve to explore your ideas. > > > > For the first option, you could use Federation. > > > > A question: > > > > You said a process A produces output to other process(es), said B. The > > process A knows in advance process B? In a message bus, process A emits > a > > message, and process B (or B1, B2, and more) subscribe to some kind of > > message. So, processes A and B (B1, B2....) are loosely couple, and can > be > > replaced, even in hot production, I guess. > > > > Angel "Java" Lopez > > @ajlopez > > gh:ajlopez > > > > On Mon, Feb 18, 2013 at 2:33 PM, MikeB_2012 > > <majb...@gmail.com<javascript:>> > wrote: > >> > >> Hi all. I'm an experienced data mining/machine learning algorithm > >> developer redirecting from programming/prototyping in Matlab (past > decade) > >> to programming in js/node.js. I'm looking for guidance as to what node > >> packages I should be considering to achieve a certain functionality. > >> > >> The functionality I'm looking for is approximately as follows: > >> > >> a) an assortment of sensors puts data on a network. Each sensor has > a > >> dedicated process that pre-processes sensor data. The processed data > is > >> then transmitted to other processes; > >> b) there are several virtual 'layers' or 'groups'. Each layer has a > >> specific purpose or goal that is attained through the asynchronous > >> processing of the processed sensor data by one or more processes; > >> c) should any process fail/crash, the remaining processes are > >> unaffected; > >> d) similarly, processes can be added to the system as required > without > >> affecting other processes; and > >> e) processes take input from other processes. For example, some > >> processes obviously will use the output of sensor pre-processing > processes. > >> But some processes will simply be taking the output of other processes. > >> > >> So you can picture this network of processes (a 'mesh' ?) with some > >> subsets of the mesh working towards common goals. The idea is vaguely > >> comparable to neural networks but with large amounts of feedback say, a > >> liquid state NN vice multi-layer feed forward NN, complex processes > vice > >> simple transfer functions at the mesh nodes, and asynchrony. > >> Within the mesh, processes are born and die, but the whole operation > >> remains largely unaffected in the sense that other processes will only > >> lose/gain information but they won't fail (cease trying to process). > The > >> latter is important because a nuance is that a given process will > decide for > >> itself what information it will use, what other processes it will > 'listen' > >> to and will have to adapt when changes occur. So processes must be > aware of > >> each other. > >> > >> Anyways, I can fake portions of all this using Matlab (in un-real-time) > >> but node.js seems to offer the potential to actually implement the idea > in > >> real-time, kind of, maybe. (I'm still learning so some of you may know > >> better.) I was optimistic with one node package, hook.io, but it has > shut > >> down. I'm happy to fork it but would need lots of help and guidance. > >> Several others were suggested including: kue, rabbitmq, zero-mq, > nssocket, > >> dnode, amino, and federation. But whereas I'd found a clear explanation > of > >> hook.io (with illustrations to confirm it seemed like what I wanted) > most > >> other packages need knowledge (eg. - reddis) that I don't yet have > >> ('federation' being the exception). > >> > >> So that's what I'm trying to do and it looks like js/node.js can help > me > >> do it. Is that a correct conclusion? If so, are there any packages or > >> approaches that you might suggest? As always, any constructive > guidance or > >> advice would be appreciated. > >> > >> -- > >> -- > >> Job Board: http://jobs.nodejs.org/ > >> Posting guidelines: > >> https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines > >> You received this message because you are subscribed to the Google > >> Groups "nodejs" group. > >> To post to this group, send email to nod...@googlegroups.com<javascript:> > >> To unsubscribe from this group, send email to > >> nodejs+un...@googlegroups.com <javascript:> > >> For more options, visit this group at > >> http://groups.google.com/group/nodejs?hl=en?hl=en > >> > >> --- > >> You received this message because you are subscribed to the Google > Groups > >> "nodejs" group. > >> To unsubscribe from this group and stop receiving emails from it, send > an > >> email to nodejs+un...@googlegroups.com <javascript:>. > >> For more options, visit https://groups.google.com/groups/opt_out. > >> > >> > > > > > > -- > > -- > > Job Board: http://jobs.nodejs.org/ > > Posting guidelines: > > https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines > > You received this message because you are subscribed to the Google > > Groups "nodejs" group. > > To post to this group, send email to nod...@googlegroups.com<javascript:> > > To unsubscribe from this group, send email to > > nodejs+un...@googlegroups.com <javascript:> > > For more options, visit this group at > > http://groups.google.com/group/nodejs?hl=en?hl=en > > > > --- > > You received this message because you are subscribed to the Google > Groups > > "nodejs" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to nodejs+un...@googlegroups.com <javascript:>. > > For more options, visit https://groups.google.com/groups/opt_out. > > > > > -- -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. 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