Limit number of concurrent connections in Apache2 - apache

Is there a way I can limit the number of concurrent connections to the Web Application running on my Apache Server.
My server version is Apache 2.2.11

Have a look at limitipconn module.

I'm not sure if it will useful to you but definitely worth a chance.
Maybe you can use the directives
MaxClients and
ListenBackLog
Although they apply to the concurrent access to the entire server, not only your application, and on a resource base.

We completely built an application layer thing that stored, checked and restricted the limit on # of application users that could be logged on concurrently.
If it got exceeded, we sent them to a 'waiting room' - worked like a charm.
So it was all application managed - we had multiple apache servers in a cluster.
We were not using the Zend clustering stuff , IMO.

Sure thing:
http://apache.ivn.cl/#bandwidth
and you can find a debian package too
libapache2-mod-bw

Related

Is there any difference between apache+Nginx as reverse proxy AND apache + another server with nginx for static contents?

We use Apache with Nginx(as reverse proxy) for more concurrency level because of the way that Nginx handles static contents and use fewer connections something that Apache lacks.
The question now is that is there any difference between the above scenario and using another server for serving static content (css,js,images,etc) with nginX and your primary server with Apache installed?
In my project there are millions of user with avatar,banner and ofcourse photo gallery. Project is nearly ready, and I want to make sure I'm on the right direction. Which scenario is the best?
EDIT:
What would happen if slow clients cause Apache to keep threads busy for longer than needed in the primary server?
One of the main purposes of nginx behind Apache is to handle slow clients to ensure that Apache doesn't have to keep its threads busy for this.
btw, I think it's relevant to the topic http://www.aosabook.org/en/nginx.html

Server configuration for high traffic website

I'm managing a hosting server and one of my customers will launch a high traffic PHP website. It's a penny auction website and we expect between 25k and 30k visitors per day.
Can you tell me please what should I change in my server configuration (PHP and Apache) to avoid problems? I'm afraid that the server crash with a large number of visitors.
Thank you
Using a lighter web server like nginx as a reverse proxy and a static content server should keep the Apache memory and CPU usage to a minimum which will be a problem on larger sites.
APC as an opcode cache will also be useful in a large site because compiling the PHP scripts to opcode is expensive.
Which Apache forking model are you using for the server? Event and Worker MPM's will probably work better for larger sites with higher concurrent connections.
How is PHP setup within Apache, i.e. FastCGI/CGI/DSO/SuPHP/FPM? SuPHP will be slowest while FastCGI, FPM and DSO will give you much better performance and allow you to use opcode caches.
If you don't need SSL support on the site a free service like https://www.cloudflare.com/ will also lessen the load on your servers.
You could put an opcode cache into use, eAccelerator is a good one for this purpose.
You may also want to consider creating Apache vHosts for static content like images/CSS/javascript to be served from. If these can be put into a CDN, then even better.
There are other tools available for benchmarking, including the Apache benchmarking tool "ab". You can use this to stress-test your site.
There are several areas in which tuning can take place, not just PHP.

nginx/apache/php vs nginx/php

I currently have one server with nginx that reverse_proxy to apache (same server) for processing php requests. I'm wondering if I drop apache so I'd run nginx/fastcgi to php if I'd see any sort of performance increases. I'm assuming I would since Apache's pretty bloated up, but at the same time I'm not sure how reliable fastcgi/php is especially in high traffic situations.
My sites gets around 200,000 unique visitors a month, with around 6,000,000 page crawls from the search engines monthly. This number is steadily increasing so I'm looking at perfomrance options.
My site is very optimized code wise and there isn't any caching (don't want that either), each page has a max of 2 sql queries without any joins on other tables, indexes are perfect as well.
In a year or so I'll be rewriting everything to use ClearSilver for the templates, and then probably use python or else c++ for extreme performance.
I suppose I'm more or less looking for any advice from anyone who is familiar with nginx/fastcgi and if willing to provide some benchmarks. My sites are one server with 1 quad core xeon, 8gb ram, 150gb velociraptor drive.
nginx will definitely work faster than Apache. I can't tell about fastcgi since I never used it with nginx but this solution seems to make more sense on several servers (one for static contents and one for fastcgi/PHP).
If you are really targeting performance -and even consider C/C++- then you should give a try to G-WAN, an all-in-one server which provides (very fast) C scripts.
Not only G-WAN has a ridiculously small memory footprint (120 KB) but it scales like nothing else. There's work ahead of you if you migrate from PHP, but you can start with the performance-critical tasks and migrate progressively.
We have made the jump and cannot consider to go back to Apache!
Here is a chart showing the respective performances of nginx, apache and g-wan:
g-wan.com/imgs/gwan-lighttpd-nginx-cherokee.png
apache does not seem to lead the pack (and that's a -Quad XEON # 3GHz).
Here is an independent benchmark for g-wan vs nginx, varnish and others http://nbonvin.wordpress.com/2011/03/14/apache-vs-nginx-vs-varnish-vs-gwan/
g-wan handles much more requests per second with much less CPU time.
NGINX is the best choice as a webserver now a days.
The main difference between Apache and NGINX lies in their design
architecture. Apache uses a process-driven approach and creates a
new thread for each request. Whereas NGINX uses an event-driven
architecture to handle multiple requests within one thread.
As far as Static content is concerned, Nginx overpasses Apache.
Both are great at processing Dynamic content.
Apache runs on all operating systems such as UNIX, Linux or BSD and
has full support for Microsoft Windows & NGINX also runs on several
modern Unix-like systems and has support for Windows, but its
performance on Windows is not as stable as that on UNIX platforms.
Apache allows additional configuration on a per-directory basis via
.htaccess files. Where Nginx doesn’t allow additional configuration.
Request Interpretation-Apache pass file System location. Nginx
Passes URI to interpret requests.
Apache have 60 official dynamically loadable modules that can be
turned On/Off.Nginx have 3rd Party core modules (not dynamically
loadable).NGINX provides all of the core features of a web server,
without sacrificing the lightweight and high-performance qualities
that have made it successful.
Apache Supports customization of web server through dynamic modules.
Nginx is not flexible enough to support dynamic modules and loading.
Apache makes sure that all the website that runs on its server are
safe from any harm and hackers. Apache offers configuration tips for
DDoS attack handling, as well as the mod_evasive module for
responding to HTTP DoS, DDoS, or brute force attacks.
When Choose Apache over NGINX?
When needs .htaccess files, you can override system-wide settings on
a per-directory basis.
In a shared hosting environment, Apache works better because of its
.htaccess configuration.
In case of functionality limitations – use Apache
When Choose NGINX over Apache?
Fast Static Content Processing
Great for High Traffic Websites
When Use Both of them -Together
User can use Nginx in front of Apache as a server proxy.

At enterprise level, is Apache Tomcat used standalone or with Apache server?

Which one of these two is most commonly used scenario? I want to use the same scenario in my learning process. thanks.
Don't know about the rest of the industry, but where I work we have Apache HTTPD front-ending for Tomcat.
Any static content is directly provided by HTTPD for performance. Pain in the neck to separate every app out, but there is a noticeable payoff.
Also, HTTPD has some nice code for cookie handling, URL rewriting, clustering and so on.
Only if we determine that there's dynamic, database-bound data to show do we forward to Tomcat, which does an admirable job there.
Has been working well for us for almost a decade. Others too, I would wager.

Why do some setups front-end Glassfish with Apache?

I've been trying to mug up on Glassfish and one thing that keeps coming up is the "how-to" on fronting Glassfish with Apache. Unfortunately, I have yet to find a description of why you would want to do this!
From my experimentation, Glassfish seems like a pretty fully featured web server-type service; but I might be missing a lot. So, is the notion of front-ending Glassfish more of a solution to integrate it with an existing architecture, or does front-ending (in a pure Java environment) provide extra benefits?
There's also another valid use case as to why we front Glassfish with Apache. Apache in this instance would function as a reverse proxy for increased security of your Glassfish. The RP is configured to allow only certain URLs to be passed through to the application server. For e.g., you may have app contexts /myApp and /myPrivApp deployed in Glassfish. In the RP server, you only configure /myApp to be passed to Glassfish. Anybody requesting for /myPrivApp would see a 404 'cos the request stops right at the RP level.
In one of my deployments, I have a bunch of WARs deployed, some for users coming from the internet, some for intranet only. I have 2 RPs running, one for internet users and the other for intranet. I configure the internet RP to only allow URLs for approved internet applications to pass through while intranet users get to see everything.
Hope that helps.
It is usually used to speed things up. Since apache is a very fast web server it is used to deliver static content. Like images, CSS files and so on. Glassfish serves the dynamic content (servlets, JSPs) in this scenario.
Another reason for using Apache as a frontend to Glassfish is the possibility to provide load balancing across a Glassfish cluster. See http://tiainen.sertik.net/2011/03/load-balancing-with-glassfish-31-and.html for details.
A other reason is that glassfish cannot run (easily) on port 80, without giving it root rights of course.
So, for most users it's easer to run a proxy (apache, nginx, varnish) some sort in front of apache and have both servers run under a normal user.
Then you have a other advantage of some configurations options of your front end. Like others mentioned, caching for example.