Related
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Closed 10 years ago.
Can anyone recommend an opensource message queue for me? like JMS, gearmand,zeroMq,Amazon SQS.
Tt would be best to satisfied the following points(not compulsive):
distributed and scalable.
supported Asynchronous message.
best to support pub/subscribe
high availability，best never drop message.
high performance
best to support php sdk, and the mq server developed by c/c++.
easy to use
the project is active.
thanks a lot!
Classic brokers:
Apache ActiveMQ — it's a JMS broker implementation from Apache. Written in Java.
RabbitMQ — popular AMQP broker implementation written in Erlang.
StormMQ — AMQP broker written in Java. Drop-in replacement for RabbitMQ (does not require changing clients).
Apache Qpid — AMQP broker, another alternative to RabbitMQ. Written in Java and C++.
Above also provide HTTP (REST API), XMPP and STOMP transports.
Other stuff:
ZeroMQ — this is not a broker, but a library. Allows for either brokered or broker-less architectures. Very light, very versatile and very fast. Written in C++.
Amazon SQS — lacks features of others. Awkward limitations like messages are not guaranteed to be in order nor to be delivered only once. No pub/sub architecture. Limited to be used in combination with AWS. Rather high latency.
distributed and scalable. — all of above
supported Asynchronous message. — all of above
best to support pub/subscribe — all except SQS
high availability，best never drop message. — all, some depending on settings
high performance — all in term of throughput, some less in terms of latency
best to support php sdk, — all of above, PHP has AMQP and STOMP clients built in, ZMQ and SQS have specific bindings.
and the mq server developed by c/c++ — only ZeroMQ, but it's not really a server
easy to use — all of above
the project is active. — all of above
ActiveMQ fits the bill. But it's not c++
ActiveMQ is the best one. There also support for C++...Refer CMS
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Closed 10 years ago.
Our company is considering moving from hosting our own servers to EC2 and I was wondering if this was a good idea.
I have seen a lot of stuff about can cloud computing (and specifically EC2) do x, or can it do y, but my real question is why would you NOT want to use it?
If you were setting up a business, what are the reasons (outside of cost) that you would choose to go through the trouble of managing your own servers?
I know there are a lot of cost calculations you can put in regarding bandwidth, disk usage etc, but there are of course, other costs regarding maintenance of your own server. For the sake of this discussion I am willing to consider the costs roughly equal.
I seem to remember that Joel Spolsky wrote a little blur on this at one time, but I was unable to find it.
Anyone have any reasons?
Thanks!
I can think of several reasons why not use EC2 (and I am talking about EC2, not grid comp in general):
Reliability: Amazon makes no guarantee as to the availability / down time / safety of EC2
Security: Amazon does not makes any guarantee as to whom it will disclose your data
Persistence: ensuring persistence of your data (that includes, effort to set up the system) is complicated over EC2
Management: there are very few integrated management tools for a cloud deployed on EC2
Network: the virtual network that allows EC2 instances to communicates has some quite painful limitations (latency, no multicast, arbitrary topological location)
And to finish that:
Cost: on the long run, if you are not using EC2 to absorb peak traffic, it is going to be much more costly than investing into your own servers (cheapo servers like Supermicro cost just a couple of hundred bucks...)
On the other side, I still think EC2 is a great way to soak up non-sensitive peak traffic, if your architecture allows it.
Some questions to ask:
What is the expected uptime, and how does downtime affect your business? What sort of service level agreement can you get, what are the penalties for missing it, and how confident are you that the SLA uptime goals will be met? (They may be better or worse at keeping the systems up than you are.)
How sensitive is the data you're proposing to put into the cloud? Again, we get into the questions of how secure the provider promises to be, what the contractual penalties and indemnities are, and how confident you are that the provider will live up to the agreement. Further, there may be external requirements. If you deal with health-related data in the US, you are subject to very strict requirements. If you deal with credit card data, you also have responsibilities (contractual, not legal).
How easy will it be to back out of the arrangement, should service not be what was expected, or if you find a better deal elsewhere? This includes not only getting your data back, but also some version of the applications you've been using. Consider the possibilities of your provider going bankrupt (Amazon isn't going to go bankrupt any time soon, but they could split off a cloud provider which could then go bankrupt), or having an internal reorganization. Bear in mind that a company in serious trouble may not be able to live up to your expectations of service.
How much independence are you going to have? Are you going to be running their software or software you pick? How easy will it be to reconfigure?
What is the pricing scheme? Is it possible for the bills to hit unacceptable levels without adequate warning?
What is the disaster plan? Ideally, it's running your software on servers in a different location from where the disaster hit.
What does your legal department (or retained corporate attorney) think of the contract? Is there a dispute resolution mechanism, and, if so, is it fair to you?
Finally, what do you expect to get out of moving to the cloud? What are you willing to pay? What can you compromise on, and what do you need?
Highly sensitive data might be better to control yourself. And there's legislation; some privacy sensitive information, for example, might not leave the the country.
Also, except for Microsoft Azure in combination with SDS, the data stores tend to be not relational, which is a nuisance in certain cases.
Maybe concern that that big a company will more likely be approached by an Agent Smith from the government to spy on everyone that a little small provider somewhere.
Big company - more customers - more data to aggregate and recognize patterns - more resources to organize a sophisticated watch system.
Maybe it's more of a fantasy but who ever knows?
If you don't have a paranoia it doesn't mean yet that you are not being watched.
The big one is: if Amazon goes down, there's nothing you can do to bring it back up.
I'm not talking about doomsday scenarios where the company disappears. I mean that you're at the mercy of their downtime, with little recourse of your own.
Security -- you don't know what is being done to your data
Dependency -- your business is now directly intertwined with the provider
There are different kinds of cloud computing with lots of different vendors providing it. It would make me nervous to code my apps to work with a single cloud vendor. that you specifically had to code for..amazon and Microsoft I believe you need to specifically code for that platform - maybe google too.
That said, I recently jettisoned my own dedicated servers and moved to Rackspaces Mosso Cloud platform (which have no proprietary coding necessary) and I am really, really pleased with it so far. Cut my costs in half, and performance is way better than before. My sql server databases are now running on 64Bit enterprise SQL server versions with 32G of ram - that would have cost me a fortune on my previous providers infrastructure.
As far as being out of luck when the cloud is down, that was true if my dedicated server went down - it never did, but if there was a hardware crash on my dedicated server, I am not sure it would be back on-line any quicker than rackspace could bring their cloud back up.
Lack of control.
Putting your software on someone else's cloud represents handing over some control. They might institute a file upload size limit, or memory limits which could ruin your application. A security vulnerbility in their control panel could get your site hacked.
Security issues are not relevant if your application does its own encryption. Amazon is then storing encrypted data that they have no way of decrypting.
But in addition to the uptime issues, Amazon could decide to increase their prices to whatever they want. If you're dependent on them, you'll just have to pay it.
Depends how much you trust your own infrastructure in comparison to a 3rd party cloud service. In my opinion, most businesses (at least not IT related) should choose the later.
Another thing you lose with the cloud is the ability to choose exactly what operating system you want to run. For example, the latest Fedora Linux kernel available on EC2 is FC8, and the latest Windows version is Server 2003.
Besides the issues raised regarding dependability, reliability, and cost is the issue of data ownership. When you locate data on someone else's server, you no longer control who views, accesses, modifies, or uses that data. While the cloud operators can limit your access, you possess no way of limiting theirs or limiting who they give access to. Yes, you can encrypt all the data on the server but you lack any way of knowing who possesses root access to the server itself and any means to stop others from downloading your encrypted data and cracking it open. You lose control over your data; depending on what type of apps you are running and the proprietary nature of the data involved, this could engender corporate security and/or liability risks.
The other factor to consider is what would happen to your company if Amazon and/or EC2 were to suddenly vanish overnight. While a seemingly preposterous position, it could happen. Would you be able to quickly fill the hole and restore service, or would your potentially revenue generating apps languish while the IT staff scramble to obtain servers and bandwidth to get them back online? Also, what would happen to your data? The cloud hard drive holding all your information still exists, somewhere, and could pose a potential liability risk depending on the information you stored there--items such as personal information, business transaction records etc.
If I was starting my own business now, I would go through the hassle of purchasing and maintaining my own severs so I retained data ownership. I could control root access to the hardware, as well as control who can access and modify the data.
Unanswered security questions.
Really, do you want your IP out there, where you're not the one in control of it?
Most cloud computing environment are at least partially vendor specific. There's no good way to move stuff from one cloud to another without having to do a lot of rewriting. That sort of lock-in puts you at the mercy of one vendor when it comes to downtime, price increases, etc. If you rent or own your own servers, hosting providers and colos are pretty much interchangeable. You always have the option of moving somewhere else.
This may change in the future, as these things become standardized, but for now tying yourself to the cloud means tying yourself to a specific vendor.
This is kind of like the "Why would you use Linux" comment I received from management many years ago. The response I got was that it is a solution in search of a problem.
So what are your goals and objectives in moving to EC2?
I'd be interested to know if you'd still want to move to a cloud, if it was your own.
Cloud computing has brought parallel programming a little closer to the masses, but you still have to understand how best to use it - otherwise you're going to waste compute cycles and bandwidth.
Re-architecting your application for most efficient use of a cloud computing service is non-trivial.
Besides what has already been said here, we have to consider uniformity across the business. Are all of you applications going to be hosted in the cloud, or only most? Is most enough to pull the trigger on using the cloud when you still have to have personnel to handle a few special servers?
In particular, there might be special hardware that you need to communicate with such modems to accept incoming data, or voice cards that make automated phone calls. I don't know how such things could be handled in a cloud environment.
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Closed 10 years ago.
We are facing a choice to use IBM MQ over SFTP for file transfer. I've heard advantages of such approach, but I've never see anyone actually using it for a large files.
So main question: how well IMB MQ can handle transfer of large files (up to 100 MB)? Is it stable? It's from mainframe to UNIX server, if it does matter.
Thanks a lot.
I've used MQ with files up to 8GB in size, without incident. You have to allocate enough space for MQ to manage them, but it works.
MQ itself offers message-based communication between programs. You can't use it directly to transfer files. People talking about "sending files via MQ" often mean that they will write the programs themselves to read from a file, send over MQ, receive from MQ and write to another file. This sounds temptingly trivial at first but quickly becomes very complex if you want it to be robust. Not recommended.
What you should be doing if you want to involve MQ in your file transfers is use one of the file-transfer products that sit upon MQ. There are a number of mature offerings, about which I know next to nothing, together with a new product from IBM itself ("Websphere MQ File Transfer Edition") which is being actively developed and recently announced an updated version (7.0.1).
To answer your specific question, I've personally used WMQFTE to transfer a file of 1000GB from an AIX machine to a Windows one, so I don't think your "large" 100MB files will be a problem :-). I don't get involved with the mainframe as much but it is very much a core platform for FTE.
Vendors have been doing File transfer over a messaging system such as WebSphere MQ for over 12 years. I have not used the IBM product. Yet, I know until recently IBM resold Metastorm’s product (under the brand PM4Data) and only recently entered the market with a first generation product.
I’ve seen Metastorm Integration Manager handle files of terabyte sizes all of the time; breaking up the messages across WebSphere MQ and performing buffers acknowledgements so not to overflow message queues or having to do a lot of MQ Administration.
Other worthwhile considerations of using messaging systems for file transfer vs. SFTP include:
Pre-and Post-Data Movement Handling - As a network transport, SFTP moves data (as can file transfer products over WebSphere MQ). To do pre- or post-movement processing, you’d have to write your own monitoring, triggering, error handling, etc. Mature vendors in the file transfer over messaging space provide infrastructure out-of-the-box for you. Depending on your application, they can also help
Audit Trail - SFTP provides often provide system-level logging. Often time, vendors providing file integration over MQ have greater audit capabilities, including the Pre- and Post-Data Movement Handling. Some vendors also offer secure web-based systems to expose certain integrations to authorized users.
Exception Handling – SFTP will give synchronous error messages from which you then code your error logic. Vendors providing file integration over MQ often provide exception capabilities ranging from "here’s a message on queue signifying a problem happened... good luck" to built-in integration to Web-based consoles or even BPM system.
Treating File Transfer as a Service – Often times, File Transfer is part of a larger business process. Some vendors leverage this to chain file transfers and even have them collaborate with human-centric processes to provide end-to-end visibility around the context of a point-to-point file transfer. Additionally, using messaging systems for file transfer helps move an organization to a more real-time, message-driven approach.
I hope the additional details give some details in your assessment. Good luck!
In one of the previous answers, there is the followng statement:
People talking about "sending files via MQ" often mean that they will write the programs themselves to read from a file, send over MQ, receive from MQ and write to another file. This sounds temptingly trivial at first but quickly becomes very complex if you want it to be robust. Not recommended.
In theory it would be nice to "sending files via MQ" because you would receive a Confirmation on Delivery (CoD) message when the recipient got (read) the file from the queue. Another benefit would be that the file would be automatically removed from the queue when the recipient got (read) it from the queue.
Do you perhaps know whether the above (or a similar) is offered by MQFTE?
Capitalwares Universal File Mover is an option here.
Also WebSphere Message Broker for Remote Adapter Deployment and WebSphere MQ File Transfer Edition are options to consider.
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Closed 10 years ago.
I'm looking for a cost effective tool for managing an web app on Ec2. Rightscale seems to the big dog and charges for it. Scalr looks like a more cost effective solution but it's hard to find out any real customer experiences..
The key aspects I'm looking for is a load balancer (http and https) and a way to automatically bring online additional web servers capacity as load increases as well as terminate the instances when load falls off.
From what I can tell, lots of people are rolling their own stuff here. We're trying to release an app and don't really want to have to fight too many heavy sys admin battles. Given the importance of performance etc I'd be grateful to hear advise and experiences from the field on this.
I am a Scalr user, a Scalr.net subscriber, and have become a Scalr enthusiast. I cannot possibly afford Rightscale.
Scalr can do what you ask.
Scalr has three images (each with 32/64 bit versions), plus a base (generic) image:
1) A load balancer image, running nginx. A highly available setup requires two of these. Scalr will manage your nameservice, and round robin between them. If one goes down, Scalr will remove it from DNS and bring up another instance. It is possible to run other load balancers, but nginx is the default.
2) Several application server images are available, running Apache/Tomcat/Rails. You setup your application here, be it PHP/Perl/Python/Java/Ruby/whatever. nginx routes requests between these instances grouped by unique user (based on IP + browser). Scalr monitors these for upness too, and replaces broken instances.
3) A MySQL database image, with automatic master/slave replication. Just deploy your schema, and Scalr handles replication and replaces defunct servers. It will also backup your data periodically. Scalr's DNS provides master and slave hostnames, so you can have your app read from the slaves and write to the master.
All of these instance types will auto-scale based on load. You start with the base image closest to what you're doing, and then you customize them for your application. For instance, we deploy our Perl/Catalyst app on the apache server instances but we serve static content from the nginx front-end servers. We had to modify our application slightly to use read/write database handles.
All in all, it took about three weeks of working through bugs in Scalr to get our application to a reliable state where I am confident that it IS highly available with Scalr. Their support was phenomenal, so the bugs didn't bother me too much, and the system is really coming along. It is approaching serious reliability.
As a side note, the best feature of Scalr is the 'Synchronize to All' feature, which auto-bundles your AMI and re-deploys it on a new instance - all without a service interruption. This saves you the time of going through the lengthy EC2 image/AMI creation process, which can otherwise make very simple admin tasks take 20 minutes. You can use this whether you are scaling your server farm or not - it would be very handy even on a single instance.
I pay Scalr.net $50 a month to host the service for me because I think it saves me time and money. The bottom line so far is this: at my last gig, we had a systems guy working on our highly available Linux DB + app server setup for a year... and he failed to achieve the kind of reliability that I achieved in three weeks. The savings by using Scalr as compared to rolling my own are extreme.
All that being said, if I could afford Rightscale, I would be using Rightscale. But the up-front fee and $500 a month make that impossible. There has been talk of waving the up-front fee in exchange for waving the consulting that it includes, but the monthly service fee isn't going anywhere.
I should mention that at the moment, sclar.net's website is down, so if I wanted to manage any of my server farms (don't have them up atm), I simply couldn't right now. It is not clear whether scaling is working for scalr.net subscribers right now, or not. Which is to say... this is perhaps not a mature solution yet. This doesn't happen often, before tonight the only downtime I've experienced were in periods of a few minutes at a time. But yeah... its down RIGHT NOW, so I must mention it :)
I would suggest a thorough reading of the support group at http://groups.google.com/group/scalr-discuss before making your decision. If you pick Scalr, be prepared to test your setup and work through any issues you have on the google group.
I will comment on your question, since giving a concrete answer is a little ambitious.
First, I see that you have haproxy on your tags. That is definitely the best load balancing software proven in EC2. There is documentation and experiences in the AWS forums on the use of haproxy.
I am unable to give you an opinion on scalr, but Rightscale is going the right direction. One of RightScale most interesting features in their roadmap is that they are a mgmt cloud system for any cloud not just EC2 of Amazon. That makes them very promising when trying to request load balancing and upscaling in need.
Also you can signup for a developer free account on rightscale and you can test some of their AMI and free scripts, they are pretty impressive.
Well, this might sound like I am working there or something, but I am a just a cloud user, no connection with them. If that crosses your mind.
I hope this helps, at least adds to the discussion.
Geo
Been on Scalr for about two months now and have slowly transitioned several production applications to the platform with good results. I strongly recommend them for quick turn around/support and value. I would like to see them improve availability of their platform.
All in all, a good fit for the original poster based on the simple use case presented.
Every service has a bad day. AWS services see down time. However, there are still users running their apps on AWS.
I have a few farms on Scalr.net and compared to Rightscale. I don't have to pay an arm and a leg.
Overall, service is very reliable. And now with the scripting engine i can setup my own scripts to govern my instances.
With Regards
Hareem Haque
Both services (rightscale and scalr) are great. The offer is not the same and the price is not the same too. But they are both what I was looking for. Regaring our budget scalr fits my needs. I found the support through a google group very strange at the beginning, but it is very fast and efficient.
Their solution is also open source (not bad) and they also have a V2 in their roadmap with support to other providers.
Wait and see, but til now, I'm very happy with it
Deciding on the right choice may not be as cut and dry as everyone expects. I have met with and heard talks from Scalr about their platform and have also listened to RightScale discuss their platform. If you have a simple SOA (App Server - Database Server - File Server), then either choice will be right for your company.
Ultimately, if you have created some custom middleware and you rely on known sockets or specific points for handshakes, you will need to consider load-balancing and auto-scaling what you can and fall back to your own solutions for what can't be managed with either of these services.
Some people say that automatic scaling won't solve the problem
I am looking into Scalr right now and although it all looks good, I decided to continue with my own scripting for the purpose of cloud management / scaling. I have 8 servers right now and am paying only the AWS fees. I use chef (self-hosted), nagios, and a lot of other tools. My databases are mysql and mongodb, load balancer is haproxy, app layer is rails. Until I need 100s of servers, I think I will just keep scriptin' ;-)
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Closed 10 years ago.
Locked. This question and its answers are locked because the question is off-topic but has historical significance. It is not currently accepting new answers or interactions.
We'd be interested to hear any experiences with the pros and cons of ActiveMQ vs RabbitMQ vs ZeroMQ. Information about any other interesting message queues is also welcome.
Edit: My initial answer had a strong focus on AMQP. I decided to rewrite it to offer a wider view on the topic.
These 3 messaging technologies have different approaches on building distributed systems :
RabbitMQ is one of the leading implementation of the AMQP protocol (along with Apache Qpid). Therefore, it implements a broker architecture, meaning that messages are queued on a central node before being sent to clients. This approach makes RabbitMQ very easy to use and deploy, because advanced scenarios like routing, load balancing or persistent message queuing are supported in just a few lines of code. However, it also makes it less scalable and “slower” because the central node adds latency and message envelopes are quite big.
ZeroMq is a very lightweight messaging system specially designed for high throughput/low latency scenarios like the one you can find in the financial world. Zmq supports many advanced messaging scenarios but contrary to RabbitMQ, you’ll have to implement most of them yourself by combining various pieces of the framework (e.g : sockets and devices). Zmq is very flexible but you’ll have to study the 80 pages or so of the guide (which I recommend reading for anybody writing distributed system, even if you don’t use Zmq) before being able to do anything more complicated than sending messages between 2 peers.
ActiveMQ is in the middle ground. Like Zmq, it can be deployed with both broker and P2P topologies. Like RabbitMQ, it’s easier to implement advanced scenarios but usually at the cost of raw performance. It’s the Swiss army knife of messaging :-).
Finally, all 3 products:
have client apis for the most common languages (C++, Java, .Net, Python, Php, Ruby, …)
have strong documentation
are actively supported
Why did you miss Sparrow, Starling, Kestrel, Amazon SQS, Beanstalkd, Kafka, IronMQ ?
Message Queue Servers
Message queue servers are available in various languages, Erlang (RabbitMQ), C (beanstalkd), Ruby (Starling or Sparrow), Scala (Kestrel, Kafka) or Java (ActiveMQ). A short overview can be found here
Sparrow
written by Alex MacCaw
Sparrow is a lightweight queue written in Ruby that “speaks memcache”
Starling
written by Blaine Cook at Twitter
Starling is a Message Queue Server based on MemCached
written in Ruby
stores jobs in memory (message queue)
documentation: some good tutorials, for example the railscast about starling and workling or this blog post about starling
Kestrel
written by Robey Pointer
Starling clone written in Scala (a port of Starling from Ruby to Scala)
Queues are stored in memory, but logged on disk
RabbitMQ
RabbitMQ is a Message Queue Server in Erlang
stores jobs in memory (message queue)
Apache ActiveMQ
ActiveMQ is an open source message broker in Java
Beanstalkd
written by Philotic, Inc. to improve the response time of a Facebook application
in-memory workqueue service mostly written in C
Docu: http://nubyonrails.com/articles/about-this-blog-beanstalk-messaging-queue
Amazon SQS
Amazon Simple Queue Service
Kafka
Written at LinkedIn in Scala
Used by LinkedIn to offload processing of all page and other views
Defaults to using persistence, uses OS disk cache for hot data (has higher throughput then any of the above having persistence enabled)
Supports both on-line as off-line processing
ZMQ
The socket library that acts as a concurrency framework
Faster than TCP, for clustered products and supercomputing
Carries messages across inproc, IPC, TCP, and multicast
Connect N-to-N via fanout, pubsub, pipeline, request-reply
Asynch I/O for scalable multicore message-passing apps
EagleMQ
EagleMQ is an open source, high-performance and lightweight queue manager.
Written in C
Stores all data in memory and support persistence.
It has its own protocol. Supports work with queues, routes and channels.
IronMQ
IronMQ
Written in Go
Fully managed queue service
Available both as cloud version and on-premise
I hope that this will be helpful for us.
source
More information than you would want to know:
http://wiki.secondlife.com/wiki/Message_Queue_Evaluation_Notes
UPDATE
Just elaborating what Paul added in comment. The page mentioned above is dead after 2010, so read with a pinch of salt. Lot of stuff has been been changed in 3 years.
It really depends on your use-case.
Comparing 0MQ with ActiveMQ or RabbitMQ is not fair.
ActiveMQ and RabbitMQ are Messaging Systems wich require installation and administration.
They offer featurewise a lot more than ZeroMQ. They have real persistent Queues, Support for transactions etc.
ZeroMQ is a lightweight message orientated socket implementation. It is also suitable for in-process asynchronous programming. It is possible to run a "Enterprise Messaging System" over ZeroMQ, but you would have to implement a lot on your own.
So:
ActiveMQ, RabbitMQ, Websphere MQ & MSMQ are "Enterprise Message Queues"
ZeroMQ is a message orientated IPC Library.
There's a comparison between RabbitMQ and ActiveMQ here. Out of the box, ActiveMQ is configured to guarantee message delivery - which can give the impression its slow compared to less reliable messaging systems. You can always change the configuration for performance if you wish and get at least as good performance as any other messaging system. At least you have that option. There's a lot of information on the forums and the ActiveMQ FAQ for configuration for scaling, performance and high availability. Also, ActiveMQ will support AMQP 1.0 when the spec is finalized, together with other wire formats, like STOMP.
Another plus for ActiveMQ is its an Apache project, so there is diversity in the developer community - and its not tied to one company.
I have not used ActiveMQ or RabbitMQ but have used ZeroMQ. The big difference as I see it between ZeroMQ and ActiveMQ etc. is that 0MQ is brokerless and does not have built in reliabilty for message delivery. If you are looking for an easy to use messaging API supporting many messaging patterns,transports, platforms and language bindings then 0MQ is definitely worth a look. If you are looking for a full blown messaging platform then 0MQ may not fit the bill.
See www.zeromq.org/docs:cookbook for plenty examples of how 0MQ can be used.
I an successfully using 0MQ for message passing in an electricity usage monitoring application (see http://rwscott.co.uk/2010/06/14/currentcost-envi-cc128-part-1/)
I'm using zeroMQ. I wanted a simple message passing system and I don't need the complication of a broker. I also don't want a huge Java oriented enterprise system.
If you want a fast, simple system and you need to support multiple languages (I use C and .net) then I'd recommend looking at 0MQ.
I can only add my 2 cents about ActiveMQ but since this is one of the most popular:
The language you want to write in might be important. Although ActiveMQ does have a client for most, their C# implementation is far from complete compared to the Java Library.
This means some basic functionality is flaky (fail-over protocol that ... well ... fails in some cases, no redelivery support) and other simply isn't there. Since .NET doesn't seem to be all that important to the project, development is rather slowish and there doesn't seem to be any release plan. Trunk is often broken so if you do consider this, you might want to consider contributing to the project if you want things to go ahead.
Then there is ActiveMQ itself which has a lot of nice features but some very strange issues aswell. We use the Fuse (Progress) version of activemq for stability reasons but even then there are a couple of weird "bugs" that you want to keep in mind:
Brokers that stop sending messages in some occasions
Journal Errors making the queue show messages that are not there anymore (they don't get delivered to the consumer but still)
Priority is still not implemented (is on the Issues list since the start of human kind)
etc. etc.
All and all, it is a pretty nice product IF you can live with its issues:
A) are not afraid to actively get involved when using .NET
B) develop in java ;-)
ZeroMQ is really with zero queues! It is a really mistake! It does not hav queues, topics, persistence, nothing! It is only a middleware for sockets API. If it is what you are looking cool! otherwise forget it! it is not like activeMQ or rabbitmq.
There is a comparison of the features and performance of RabbitMQ ActiveMQ and QPID given at
http://bhavin.directi.com/rabbitmq-vs-apache-activemq-vs-apache-qpid/
Personally I have tried all the above three. RabbitMQ is the best performance wise according to me, but it does not have failover and recovery options. ActiveMQ has the most features, but is slower.
Update :
HornetQ is also an option you can look into, it is JMS Complaint, a better option than ActiveMQ if you are looking for a JMS based solution.
I wrote about my initial experience regarding AMQP, Qpid and ZeroMQ here: http://ron.shoutboot.com/2010/09/25/is-ampq-for-you/
My subjective opinion is that AMQP is fine if you really need the persistent messaging facilities and is not too concerned that the broker may be a bottleneck. Also, C++ client is currently missing for AMQP (Qpid didn't win my support; not sure about the ActiveMQ client however), but maybe work in progress. ZeroMQ may be the way otherwise.
I've used ActiveMQ in a production environment for about 3 years now. While it gets the job done, lining up versions of the client libraries that work properly and are bug free can be an issue. Were currently looking to transition to RabbitMQ.
There is some discussion in the comments of this blog post, about Twitter writing their own message queue, which may be interesting.
Steve did extensive load and stress
testing of ActiveMQ, RabbitMQ, etc.
ActiveMQ is actually quite slow (much
slower than Kestrel), RabbitMQ
consistently crashes with too many
producers and too few consumers.
You probably won't have Twitter-like load initially however :)
Few applications have as many tuning configurations as ActiveMQ. Some features that make ActiveMQ stand out are:
Configurable Prefetch size.
Configurable threading.
Configurable failover.
Configurable administrative notification to producers.
...
details at:
http://activemq.net/blog
http://activemq.apache.org
If you are also interested in commercial implementations, you should take a look at Nirvana from my-channels.
Nirvana is used heavily within the Financial Services industry for large scale low-latency trading and price distribution platforms.
There is support for a wide range of client programming languages across the enterprise, web and mobile domains.
The clustering capabilities are extremely advanced and worth a look if transparent HA or load balancing is important for you.
Nirvana is free to download for development purposes.
Abie, it all comes down to your use case. Rather than relying on someone else's account of their use case, feel free to post your use case to the rabbitmq-discuss list. Asking on twitter will get you some responses too. Best wishes, alexis
About ZeroMQ aka 0MQ, as you might already know, it's the one that will get you the most messages per seconds (they were about 4 millions per sec on their ref server last time I checked), but as you might also already know, the documentation is non existent. You will have a hard time finding how to start the server(s), let alone how to use them. I guess that's partly why no one contributed about 0MQ yet.
Have fun!