ZeroMq IRC Log

Friday May 27, 2011

[Time] Name	Message
[00:21] taotetek	zedas: hey
[00:21] taotetek	zedas: that just cleared something up for me, thank you :)
[00:55] Scramblejams	Hi all. Erlang (and zmq) noob here, planning to use Erlang on an upcoming project and I have a zmq question. When you're starting out, building a little Erlang program that's distributed among a few machines, at what point do you say to yourself, I'd rather use zmq than Erlang's built-in process-based message passing? Is it a question of outgrowing what Erlang offers? Or is it something differenT?
[13:29] cods	Hi. I've a server that must sent command to specific clients. I use a PULL and a PUB socket on the server, then a PUSH and a SUB socket on the client. Each clients subscribe to message targeted at it and send feedback through PUSH (and can also sent notification not related to a command to the server). Does it make sense to use these type of sockets in this case?
[13:29] cods	I ask because I've not seen a similar example in the guide
[13:30] cods	thus wondering if I'm missing a simpler/better pattern
[13:46] nicolas	in the guide, the missing message problem solver diagram says 'start the SUB after the PUB' shouldn't it be before ?
[13:47] nicolas	because when no, the arroy points to 'start all SUB first ..'
[13:47] nicolas	*arrow
[13:57] sustrik	nicolas_: ask the question on the mailing list
[13:57] sustrik	if it's wrong, it's going to be fixed
[14:13] blithe	Gave a talk at my workplace on zmq on Wednesday. Everyone seemed pretty jazzed up by it. Thanks for making zmq so awesome. ;-)
[14:15] sustrik	:)
[14:15] sustrik	was it a public event?
[14:16] blithe	Negative, but I'm going to polish it up and take it to a few user groups around here.
[14:16] sustrik	great
[14:16] sustrik	it's good to announce it on 0mq mailing list as well
[14:16] sustrik	some more people may turn up
[14:17] blithe	For sure!
[14:17] blithe	I love how demo-able zmq is.
[14:17] blithe	Lots of fun examples to mess with people's minds.
[14:18] sustrik	i always thought that projects with no GUI are not good for demos :)
[14:19] ianbarber	zeromq is pretty easy to demo, it just all looks kind of magic, especially disconnected sockets and so on
[14:20] sustrik	ah, seem tweets about lecturing in dark
[14:20] sustrik	what have happened?
[14:21] blithe	ianbarber: Your talk was part of my inspiration for this talk.
[14:21] ianbarber	i got a few minutes in to my talk, had showed a basic req rep thing, and the power went out
[14:21] ianbarber	blew a transformer down the road
[14:21] sustrik	0mq is powerfull...
[14:21] ianbarber	once i realised it wasn't coming back i just kind of talked loud (PA down as well) and made a lot of analogies :)
[14:22] blithe	hahaha
[14:22] sustrik	must have been fun
[14:22] ianbarber	it was entertaining. everyone's laptops still worked, and the wifi was on UPS, so I was pointing people at git hub for code to go along with what i was saying :)
[14:23] sustrik	:)
[14:24] ianbarber	blithe: cool! mail the list if you get any video/audio/slides on line, would love to see your talk
[14:25] blithe	Ah, and you're even in Chicago too!
[14:25] ianbarber	oh are you round there? i did consider mailing the list about a meetup, but didn't in the end
[14:26] blithe	Yeah, I work in the city.
[14:26] ianbarber	cool
[14:26] ianbarber	i'm flying out today though, that's a shame
[14:26] blithe	:-(
[14:27] blithe	Just in town for the week?
[14:27] ianbarber	yeah, just came in for the php tek conference
[14:27] ianbarber	spent a couple of days in town on sun/mon though (went on the ferris wheel and played minigolf on navy peer, pretty hardcore)
[14:29] blithe	Cool beans dude, where are you from?
[14:29] ianbarber	UK
[14:30] ianbarber	one of the guys at the talk was into the new ipython stuff which is built using zeromq for it's messaging, that seems very cool. I need to pay attention to those kind of posts on the lists.
[14:31] sustrik	what was he using it for, scientific computation?
[14:31] blithe	Do you find it hard to dispell people's normal assumptions about MQ systems when you talk?
[14:31] ianbarber	sustrik: he was just interested in it, but yeah that's the kind of aim of it i believe.
[14:32] sustrik	i see
[14:32] ianbarber	blithe: i hammer on the point that it's not a broker, it's not a service
[14:32] ianbarber	i also like pieterh's analogy - most MQs are like SVN, essentially centralised, ZeroMQ is like git, essentially decentralised
[14:33] ianbarber	often get feedback that people had just assumed it was like activemq etc. though
[14:33] ianbarber	(before the talk)
[14:34] sustrik	actually, the name is pretty misleading
[14:34] sustrik	it shouldn't be called MQ probably
[14:34] sustrik	but it's too late to change that now
[14:34] ianbarber	yeah
[14:38] taotetek	ianbarber: yup (as to the not a broker)
[14:39] blithe	sustrik: Someone asked me about production uses of zmq, I could only speak in generalities about how it was "Written by the original guys who wrote AMQP (to solve some of its shortcomings) and was written with the financial industry in mind." Any compelling production uses that come to mind I could talk about in the future?
[14:39] taotetek	ianbarber: that's why we wrote input / output plugins for zmq for rsyslog - we're experimenting with using rsyslog when we need durability / queueing / etc
[14:39] ianbarber	taotetek: that is very cool by the way, good work on that.
[14:40] taotetek	ianbarber: we use zmq for handing work out to distributed processing systems, etc
[14:40] taotetek	ianbarber: and rsyslog for the routing backbone
[14:40] ianbarber	cool
[14:40] taotetek	ianbarber: thanks! I wish I could take credit for the actual code... I have a very good c contractor who works with me
[14:41] ianbarber	blithe: there's some cool stuff going on with it. one of the most fun I've seen is mikko's lecture recorder - uses a kinect sensor to control a camera to track a lecturer around a classroom - all messaging is via zeromq (frame available, control messages etc.)
[14:42] blithe	That'd be a fun demo to see. ;-)
[14:42] ianbarber	i think there's some videos on line somewhere
[14:44] ianbarber	someone pinged me a couple of cool startups using it the other day as well, but the names escape me, was a hackathon with open bar last night which hasn't helped :)
[14:51] Seta00	http://www.egeniq.com/2010/12/23/unattended-lecture-recording-with-computer-vision/
[14:56] blithe	Thanks.
[15:25] vy	Hi! Has anybody ever tried ZeroMQ on an embedded platform? (Ala OpenWRT.) What are its system requirements? Memory footprint, binary size, etc.
[15:54] blithe	One thing I've been confused about with ZMQ envelopes/multi-part messages: https://gist.github.com/995542
[15:57] sustrik	re
[15:57] sustrik	blithe: some people have explained there use cases on the mailing list
[15:58] sustrik	other than that it's hard to find out who's using an open source product
[15:58] sustrik	i guess it's used a lot in financial services but these guys are not exactly open about what they are doing
[15:59] blithe	haha, very true
[16:00] sustrik	the ipython guys are doing scientific computing afaik
[16:01] sustrik	loggly is doing logging as a service
[16:02] sustrik	dunno, maybe you should google it
[16:03] blithe	;-)
[16:04] sustrik	as for the message parts the thing is specific to a messaging pattern
[16:05] sustrik	here's how it works for req/rep: http://www.zeromq.org/tutorials:xreq-and-xrep
[16:06] blithe	Thanks sustrik
[17:52] michelp	pieterh, did you have any trouble with your arrangements to get here? train? hotel?
[22:58] CIA-31	pyzmq: 03MinRK 07master * re4212a2 10/ setup.py : add note about ldconfig on failed zmq detection - http://bit.ly/kphP1Z
[22:58] Rod	Hi!
[22:59] Rod	Anyone using 0mq from perl here?