I need a point to start from. I read from Yakov Fain about a performance break through with jetty and blazeds.
I realized that we already have some trouble with about 1200 concurrent users, some consumers dont get messages and cpu is under heavy fire.
Did somebody already tried this Nio with BlazeDS?
Did this work with Tomcat too?
Where to start and what do I need to improve messaging performance?
Thank you so much!!!
I would suggest before you go down the road of customizing BlazeDS to support NIO that you profile your application and verify were the hotspots are. Have you verified that it is the BlazeDS networking stack that is causing lost messages? Have you profiled your code to see if there are optimizations that can be done to better optimize message handling?
Some actually contend the Java NIO doesn't actually improve through-put - http://paultyma.blogspot.com/2008/03/writing-java-multithreaded-servers.html
I say this because BlazeDS does not support NIO only the commercial version of the server does - LCDS. What LCDS does actually set-up it's own NIO sockets and manages requests through these connections, bypassing the standard servlet stack. To get NIO support Yakov said "To support thousands concurrent users you also need to customize networking layer of BlazeDS" I would be willing to guess this customized networking layer is not production ready and is more of a prototype because it is extremely difficult to reliably customize the networking layer of any server.
Related
I have to connect an old but critical software to RabbitMQ. The software doesn't support AMQP, but it can do HTTP Requests.
Does RabbitMQ support plain HTTP? Or should I use a "proxy" or "app" that actively transforms the HTTP Requests to AMQP 1.0 and pushes it to the RabbitMQ server?
https://www.rabbitmq.com/management.html
The management plugin supports a simple HTTP API to send and receive messages. This is primarily intended for diagnostic purposes but can be used for low volume messaging without reliable delivery.
As mentioned, it's designed for very low loads, but it may be usable. If you need higher loads, then by all means cast around for a library that does the job and create a proxy. Most languages will have something. I've personally created a lightweight API using Lumen and https://github.com/bschmitt/laravel-amqp to tie a few disparate services together in the past, and it seems to work very well.
It is possible not but really recommended depending on load. You have three options really, two of which are web socket based and one that seems like what you're looking for. I'd suggest starting with the rabbitmq docs.
I want to create a web app using React as the front end technology. A requirement for the app is that the server will be able to update all the clients with information about changes (not have to be an exact real time, but should update after no more than 10 seconds).
Solutions like clients requesting updates from the server every several seconds are out of the question.
Requirements:
1) The server's should be implemented with either .NET or with Node.js.
2) The connection MUST be secured via port 443 of the IIS.
I read a bit about Micorsoft's SignalR and about Pusher Channels which seems to provide exactly the kind of service I require.
Could you please elaborate about what exactly are the differences between them? When should I choose each? Which of them got more community support? Which is easier to implement? Stuff like that...
Both SignalR and Pusher Channels ultimately both use websockets to deliver messages to clients, so both should meet your requirements to deliver messages to clients in realtime.
1) Both offerings also meet your requirements for both library support:
SignalR supports .NET:
https://dotnet.microsoft.com/apps/aspnet/signalr
Pusher Channels has server support for both nodejs and .NET:
https://github.com/pusher/pusher-http-node
https://github.com/pusher/pusher-http-dotnet
2) Both offerings also meet your requirements for sending messages over TLS/WSS:
SignalR:
https://kimsereyblog.blogspot.com/2018/07/signalr-with-asp-net-core.html
Pusher Channels:
Securing Pusher's messages
In terms of the differences between them this depends on your implementation, if you just run SignalR on your own ISS server then it will be down to you to manage all of the websocket connections and all of the scaling challenges that come with this.
However similar to how Channels works, SignalR also has a managed websocket service, so you do not need to manage the connections or scaling. You just make an API request with the message you want to send to either Channels or SignalR and this message is then broadcast to the interested clients connected by websockets. In this scenario you do not manage the websocket connections yourself.
However in terms of pricing Channels appears to be far more competitive (especially the free offering), so if you are looking at the managed offering Channels looks to be a better value proposition:
https://azure.microsoft.com/en-gb/pricing/details/signalr-service/
https://pusher.com/channels/pricing
Both offerings look fairly similar in terms of implementation (assuming you are using the managed service). The complexity would increase if you implement SignalR on ISS:
https://learn.microsoft.com/en-us/aspnet/core/signalr/scale?view=aspnetcore-2.2
In terms of support Pusher has a free application support offering:
https://support.pusher.com/hc/en-us
Hope this helps!
This presentation has some answers A 10 Minute Guide to Choosing a Realtime Framework
I am having Flex + Spring BlazeDS Integration + Java combination for my project. This project is deployed on weblogic server. As we know whenever a client connects to blazeDS it blocks one thread on the server and it is a limitation for the maximum number of concurrent clients for one BlazeDS instance.
In my case I am supposed to have around 300,000 updates every hour and at any moment of time around 500 concurrent client can be there. In extreme case it can be all 1500 clients connected to the application. What is the best possible solution for that?
If I try to convince my clients to use LCDS they would like to know the exact number that our current setup can support. For that I tried to use neoload but could not make much progress in that direction.
So If any body has used such a setup and can advise me what shall I do, it would be really great!!
After some research (we may have a similar situation, it seems that blazeDS is not able to use NIOs. Here is a link about it. They offer a solution that seems broken with newer versions of tomcat. So I guess blazeDS is not the one to use in your usecase.
If you cannot go with LCDS, a good free solution is graniteDS, supporting asynchronous servlets
The short story: me and friend are making a multiplayer action game and we thought playn would be great for this. Android, java and HTML5 support is the most important ones but we don't want to cut out the others if not necessary.
The problem is now when we want to implement the networking part of it. We have implemented our own capable server and thought we would use long polling http requests for communication. We estimate now we need some way to have one thread running for the communication that use messages and two multithread safe queues. One queue for incoming messages that the update() part can consume from and one queue for outgoing messages to the server.
Is there any way to implement this without losing platform support? Or any other idea how we can implement this?
PlayN currently has no cross-platform support for persistent socket connections to a server. You will need to implement your own cross-platform abstraction. You can use WebSockets for the HTML5 backend, and you can look for a WebSockets library for Android and whatever other platforms you intend to support.
You can also use the Nexus library, which is designed to work with PlayN and provide client/server communication. However, it raises the level of abstraction substantially beyond passing simple messages between the client and server, so it might be easier to just implement your own simple WebSockets based communication than to learn how Nexus works.
I'm developing a multi-player game and I know nothing about how to connect from one client to another via a server. Where do I start? Are there any whizzy open source projects which provide the communication framework into which I can drop my message data or do I have to write a load of complicated multi-threaded sockety code? Does the picture change at all if teh clients are running on phones?
I am language agnostic, although ideally I would have a Flash or Qt front end and a Java server, but that may be being a bit greedy.
I have spent a few hours googling, but the whole topic is new to me and I'm a bit lost. I'd appreciate help of any kind - including how to tag this question.
If latency isn't a huge issue, you could just implement a few web services to do message passing. This would not be a slow as you might think, and is easy to implement across languages. The downside is the client has to poll the server to get updates. so you could be looking at a few hundred ms to get from one client to another.
You can also use the built in flex messaging interface. There are provisions there to allow client to client interactions.
Typically game engines send UDP packets because of latency. The fact is that TCP is just not fast enough and reliability is less of a concern than speed is.
Web services would compound the latency issues inherent in TCP due to additional overhead. Further, they would eat up memory depending on number of expected players. Finally, they have a large amount of payload overhead that you just don't need (xml anyone?).
There are several ways to go about this. One way is centralized messaging (client/server). This means that you would have a java server listening for udp packets from the clients. It would then rebroadcast them to any of the relevant users.
A second way is decentralized (peer to peer). A client registers with the server to state what game / world it's in. From that it gets a list of other clients in that world. The server maintains that list and notifies the other clients of people who join / drop out.
From that point forward clients broadcast udp packets directly to the other users.
If you look for communication framework with high performance try look at ACE C++ framework (it has Java bindings).
Official web-site is: http://www.cs.wustl.edu/~schmidt/ACE-overview.html
You could also look into Flash Media Interactive Server, or if you want a Java implementation, Wowsa or Red5. Those use AMF and provide native functionality for ShareObjects including synching of the ShareObjects among connected clients.
Those aren't peer to peer though (yet, it's coming soon I hear). They use centralized messaging managed by the server.
Good luck