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==Infrastructure== | ==Infrastructure== | ||
===[http://knowledgehub.zeus.com/docs Zeus]=== | |||
Zeus is the replacement for Netscaler | |||
===[http://www.citrix.com/English/ps2/products/product.asp?contentID=21679 Netscaler]=== | ===[http://www.citrix.com/English/ps2/products/product.asp?contentID=21679 Netscaler]=== | ||
''[http:// | ''[http://support.citrix.com/article/CTX112300 Manuals and Release Notes]'' | ||
One of the best ways to lower the load on a server is to reduce its traffic, which is essentially the goal of the netscaler. The netscaler sits between the webservers and provides: | One of the best ways to lower the load on a server is to reduce its traffic, which is essentially the goal of the netscaler. The netscaler sits between the webservers and provides: | ||
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* SSL offloading: SSL connections are made with the netscaler (which has hardware dedicated to setting up SSL connections) instead of the webservers. Connections to the webservers are always over http (if you're writing code that is expecting https, realize that the webheads never see the ssl connection) | * SSL offloading: SSL connections are made with the netscaler (which has hardware dedicated to setting up SSL connections) instead of the webservers. Connections to the webservers are always over http (if you're writing code that is expecting https, realize that the webheads never see the ssl connection) | ||
* Content Caching: Outbound content (webhead -> internet) is cached according to rules on the netscaler. To get the current set of rules, you'll need to talk to IT. The default set of rules is on page 336 of the [http:// | * Content Caching: Outbound content (webhead -> internet) is cached according to rules on the netscaler. To get the current set of rules, you'll need to talk to IT. The default set of rules is on page 336 of the [http://support.citrix.com/article/CTX112300 2nd install guide] | ||
* Some monitoring/balancing of the web servers. Webservers that respond faster are given more traffic. If a webserver becomes unresponsive, the netscaler will discontinue sending requests to it until it comes back to life. | * Some monitoring/balancing of the web servers. Webservers that respond faster are given more traffic. If a webserver becomes unresponsive, the netscaler will discontinue sending requests to it until it comes back to life. | ||
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Currently, development is done on standalone virtual machines running all the software (mysql, apache, etc.). Generally, development servers are only available in the VPN. | Currently, development is done on standalone virtual machines running all the software (mysql, apache, etc.). Generally, development servers are only available in the VPN. | ||
== Coding == | == Coding == | ||
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==Load Testing== | ==Load Testing== | ||
Once a site is written, it's a good idea to load test it to get an idea of how many hits per second it can handle. Something to remember with all the programs is the infrastructure you're testing on. If you're testing from one machine to one server, that will give you an idea what your code can do, but it's definitely not the same as a cluster of machines. Same with server->database connections. | |||
===[http://httpd.apache.org/docs/2.0/programs/ab.html ab]=== | |||
A pretty basic/simple benchmarking program. It works, but it's important to realize that it isn't distributed, so you might be maxing out the source machine and not the server. | |||
===[http://grinder.sourceforge.net/ Grinder]=== | |||
This is a good idea (distributed benchmarking), but we didn't get it to work as advertised. Overall disappointing - maybe revisit when it matures. | |||
===[http://github.com/oremj/logreplay log_replay]=== | |||
This is a python script that oremj wrote. Given a log, it will replay the hits. This gives you the advantage of replaying an actual set of hits across multiple pages, giving you a good distribution of hits. This is mostly useful if you have actually had people using the site. | |||