Pretty straightforward question. I can't find it in the docs or the spec.
From the AMQP spec, section 1.1:
If set, the server will not respond to the method. The client should not wait for a reply method. If the
server could not complete the method it will raise a channel or connection exception.
Related
Does SETNX work properly in REDIS cluster? or it is meant to be work only in single instance REDIS?
Is there a official documentation regarding this? Official doc does say that it is discouraged to use for locking in favor of distributed locking.
SETNX is fully supported by any Redis topology, including stand-alone and cluster. The official docs says the suggested locking pattern mentioned there is discouraged, not the command itself:
[...] The following pattern is discouraged in favor of the Redlock algorithm which is only a bit more complex to implement, but offers better guarantees and is fault tolerant.
[...]
I've taken a look at openCypher specs. And I wonder if I can use all of the clauses any principles from openCypher in Memgraph.
Memgraph follows openCypher specifications, but there are some minor differences in implementation. You can find the exact list of differences listed on the Memgraph documentation site.
Can someone explain the significance of Hazelcast Custom Serialization techniques :-
StreamSerializer
ByteArraySerializer
I have gone through Hazelcast official documentation but it's not very clear from that.
There's a nice blog writeup at https://hazelcast.com/blog/comparing-serialization-methods
I am very much new to activemq. I was trying to use activemq broker for subscribe/publish messages. But as for lack of experience I have no idea how to do it or if its really possible to do it. I googled a lot but unfortunately there is no suitable example for this type of functionality. So I was hoping may be someone here can put some light on it. Can any one here can give me some example of how to do it? or may be some link to online documentation. I have already tried apache activemq broker documentation. But it was not helpful, or may be I dont have that much experience to take help from it.
What you are interested in is done using topics. The reason that you haven't necessarily seen a description of it on the ActiveMQ site is that it's a foundational thing that is assumed that readers know about.
If you are looking at an introduction into messaging using Java, the best place is Oracle's JMS tutorial. Afterwards take a look at the code in the examples directory of an ActiveMQ installation. Alternatively, ActiveMQ in Action is a great book to get you heading in the right direction.
If you are using a language other than Java, ActiveMQ supports the STOMP protocol for which there are a large number of implementations in various languages.
Hope that helps.
I'm looking for articles and references that give an overview of 'queueing' (I'm probably not even using the right term here). I'm hoping for an introductory styled guide through a world of Redis, RabbitMQ, Celery, Kombu, and whatever other components exist that I haven't read about yet, and how they fit together.
My problem is I need to queue up background tasks for issued by my Django website, and every blog and article I read recommend different solutions.
Lots of options available to you, and your choice will likely come down to personal preference and what dependencies you feel comfortable installing.
I'll give a vote for Redis. I evaluated RabbitMQ, ActiveMQ, HornetQ, and Redis and found Redis to offer the best mix of ease of installation, simplicity, and performance.
It's technically not a message queue, but the push/pop primitives for the list types provide atomic queue-like operations, so it can effectively be used as a queue. It has worked well for us.
One python specific project on top of Redis you might look at:
http://richardhenry.github.com/hotqueue/tutorial.html
Very simple. But again, all the other options, like Celery, are viable too.
RabbitMQ has a good introduction here: http://www.rabbitmq.com/getstarted.html There's examples in Python, even.
HornetQ has a very good documentation, and it's simple to install.
You can find the documentation at www.hornetq.org, and you would have several examples available with the distribution.