Am working on wso2esb and created several proxy services and using Apache 2 proxy to call this services, So every request of ESB goes through the Apache2 proxy ,After an usage of 10-15 days the performance becomes slow day by day along with all the other servers performance which are using Apache 2 server are also slow.
Tried reloading and restarting Apache server but no change in performance.
When i restarted the esb server then it was back to normal stage, Doesn't know what esb is holding and causing this performance issue.
what can be done to resolve this with out restarting the esb server.
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Backstory: A couple of years ago my group changed the server on which coldfusion runs to Apache instead of IIS. I changed my dev environment to run CF on Apache httpd and everything was fine. Later we changed the session variables to j2ee, but I have never been able to get j2ee to work on dev so I am still using regular session variables on dev. Lately I am getting session persistence failure on test but I can't reproduce on dev. In looking for differences in CF server settings between test and dev I discovered that test is running on Tomcat while dev is running on Apache httpd.
My problem real problem is how to get j2ee session vars to work on dev. My question right now is how do I change my server from Apache httpd to the Tomcat that is built in with CF 10? Is there a way to do this without starting over with a fresh install of CF 10 as those are the only instructions I can find?
System: Windows 7
IIS and Apache are not (for Coldfusion, anyway) application servers. They are your front-end web servers. Your 'application server' in this setup is the software running the "application" of Coldfusion via servlets, and that's Tomcat.
While it is possible to use CF's builtin Tomcat server as your front-end web server, it isn't advisable, and it's almost certainly got nothing to do with your problem. Apache is more than capable of doing what you need and a problem with J2EE session variables is going to be related either to your JVM (are you using more-or-less the same version as your production server?) or to Tomcat itself.
Think about how J2EE sessions work. A request comes in and hits your front-end server (httpd), which, presumabl through mod_proxy or mod_jk, hands that connection over to Tomcat. Until this happens, that your system is even running a JVM isn't relevant -- neither Apache nor IIS care about Java. I wouldn't go so far as to say that it's impossible for an Apache problem to be monkeying with your session variables, but it would be pretty low on my list of suspects.
Once Tomcat (and then CF) get involved, then your JVM is doing all the work, so that's where I'd look. I'd also have a look at CF logs and Tomcat logs.
To properly answer your question, though, if you want to remove Apache from the loop, you're looking at Tomcat's server.xml and web.xml in /cfusion/runtime/conf - you'd need it running on port 80 (or else reconfigure Apache to just pass all requests to Tomcat instead of only CFML, but that doesn't really do what you asked about since Apache is still involved). You'd also have to reproduce your entire Apache configuration in Tomcat, which I've never done and wouldn't recommend, but that's the direction you'd need to investigate.
Much better to work on solving your session problem. Killing Apache is just collateral damage here.
I am new to Web Service and LAMP Stack.Currently I am working on a Web Application.It is a PHP Based Application that uses Apache Tomcat Web Server 8.0.26 ,MySQL Database ad Linux operating system(LAMP Stack).It has Web Services in Spring.
Following are the issues I am facing with the Application:-
1) Responses are slow over a period of few weeks from a web service hosted on tomcat.
Temporary Solution:-The problem is solved when we restart the Web Server.
2) What are the tools we can use to monitor tomcat / performance ?
Regards
Kaustubh
Take the dump of heap usage before and after of slow down and analyze. And also check your connection pooling with the database, check whether logs are getting rotated properly or not, check the number of active sessions in tomcat admin console.
We currently run a SaaS application on apache which server ecommerce websites (its a store builder). We currently host over 1000 clients on that application and are now running into scalability issues (CPU going over 90% even on a fairly large 20 core 80GB ram + all SSD disk server).
We're looking for help from an nginx expert who can:
1. Explain the difference between running nginx as a web server vs. using it like a reverse proxy. What are the benefits?
2. We also want to use nginx as a load balancer (and have that already setup in testing), but we haven't enabled cacheing on the load balancer. So while its helping redirect requests, its not really serving any traffic directly and it simply passes through everything to one of the two apache servers.
The question is that we have a lot of user-generated content coming from the apache servers, how do we invalidate the cache for only certain pages that are being cached by nginx? If we setup a cron to clear this cache every 1 minute or so, it wouldn't be that useful... as cache would then be virtually non existent.
--
Also need an overall word on what is the best architecture to build for given the above scenarios.
Is it
NGINX Load Balancer + Cacheing ==> Nginx Web Server
NGINX Load Balancer ==> Nginx Web Server + Cacheing ?
NGINX Load Balancer + Cacheing ==> Apache Web Server
NGINX Load Balancer == > Apache Web Server (unlikely)
Please help!
Scaling horizontally to support more clients is a good option. Its recommended to first evaluate what is causing the bottleneck, memory within the application, long running requests etc.
Nginx Vs other web servers: Nginx is a HTTP server and not a servlet engine. Given that, you can check if it fits your needs.
It is a fast web server. You need to evaluate the benefits of using it as a single stand alone webserver against other web servers. Speed and memory could help.
Nginx as a load balancer:
You can have multiple web server instances behind nginx.
It supports load balancing algorithms like round robin, weighted etc so the load can be distributed based on the resource availability.
It helps in terminating ssl at Nginx, filter requests, modify headers,
compression, application upgrades wihtout downtime, serve cached content etc. This frees up resources on the server running the application. Also separation of concerns.
This setup is a reverse proxy and the benefits to it.
You can handle cache expiry with nginx. nginx documentaion has good details http://nginx.com/resources/admin-guide/caching/
I am trying to understand the working of HTTP , IIS and sql server.
I am having an IIS 7 server in my environment which is interacting with a sql database server.
The architecture is
Apache ----> IIS -----> SQL server
The Apache is a reverse proxy server which is sending the HTTP request to the IIS server and from there IIS server is interacting with the SQL database connecting by different application pools for different applications.
My query is if some request has been forwarded by the Apache server and it has reached the IIS ; after that, if the network between the Apache and IIS is having any packet drops ;
Will that have any affect to the performance of IIS and database server?
Will there be any long running queries in the worker process of the IIS? Because my concern is what will happen after the queries that has successfully executed in the Database server. But since the network between the IIS and Apache is broken how can they be forwarded further to the Apache and further to the end user.
Will these queries keep on holding the resources till they are forwarded from IIS to Apache? Because they have successfully completed their tasks but because of network issue they are not being forwarded further. Or are such request stacked up somewhere by the IIS to free up the resources for the upcoming requests??
Once a request has reached IIS it will go and do the required actions, and format the reply. It will try to send the reply to the requestor but if the link has gone, it will be unable to. It will then abandon the request. Resources it is holding for that request will be freed.
To get the data it had for you, Apache has to repeat the request.
I am running tornado behind apache. I have created proxy server.
ProxyRequests On
ProxyPass /chat/ http://localhost:8888/chat/
This code works great and pass all my requests to tornado and returns the response back to client.
Now, I am using tornado for long polling. Some of the requests which finishes in a short interval of time say less than 1 minute this reverse proxy works fine. But certain long polling requests this gives 502 proxy error. The reason for this proxy error is that Apache can hold long polling request for just one minute(by default). It closes the request and hence proxy error is received.
Now, I modified the directive to
ProxyRequests On
ProxyPass /chat/ http://localhost:8888/chat/ timeout=12000
i.e I changed the default timeout to 12000 seconds.
This is currently working fine for me. Bu this is not the best solution to the issue. Ideally long polling requests can exceed any timeout specified. So my questions are
How to make the timeout infinite ? i.e the request is never closed by Apache.
Please also comment: whether the performance of tornado is degraded by going through Apache as proxy server?
I experienced a similar issue with Nginx and solved it the same way as you did. But I changed the timeout to 1 day as it was sufficiently large in my case.
I think you cannot do away with this. The rationale behind this is that Apache (or any proxy server for that matter) has to maintain its performance, which it clearly can't if it has to hold stale or inactive connections. You'd rather let your proxy server proxy more active connections than inactive connections.
Therefore, there is no way to turn off the ProxyTimeout in Apache or even in Nginx (configured using proxy_read_timeout). So if your proxied server is not sending any response within the timeout, then either your application server is taking too long to respond or there is something wrong with your application server or the client is not request for any response. In the first case, you can make safe estimates to set an appropriate timeout. In the second case, you need to fix your application server. And in the third case, you must gracefully handle the situation on the client and reconnect if required.
Coming to your second question, there shouldn't be any difference other than the latency involved between your Apache and your Tornado server. You can very well expose your Tornado server directly to the world but that will come with a few challenges:
1. More ops work - make sure that Tornado process is always up and running.
2. Proxying and load balancing will become more difficult.
3. Worse security as YOU have written that code instead of thousands of expert contributors. So you should not be thinking of running this server as root every. But you can still sort of safely do the same with Apache or Nginx.
Of course the above problems are solvable, but why solve an already solved problem. :)