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Is there a tool (preferably a web service) that can stress test our site? We're having problems with our site going down once we have about 100 concurrent users. Forums seem to suggest I need to tweak my httpd.conf. I plan to try to tweak httpd.conf, but need to know if the tweaks actually did anything. So stress testing it after each configuration change might be my plan of attack. Suggestions?

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up vote 8 down vote accepted

If you're using Apache you can use a utility called ab (Apache Bench).

From the fine manual:

ab is a tool for benchmarking your Apache Hypertext Transfer Protocol (HTTP) server. It is designed to give you an impression of how your current Apache installation performs. This especially shows you how many requests per second your Apache installation is capable of serving.

It's that last bit that you'll be interested in.

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Example usage: ab -n 100 -c 20 http://... – Coops Aug 9 '11 at 8:37

You could also try JMeter

Apache JMeter may be used to test performance both on static and dynamic resources (files, Servlets, Perl scripts, Java Objects, Data Bases and Queries, FTP Servers and more). It can be used to simulate a heavy load on a server, network or object to test its strength or to analyze overall performance under different load types. You can use it to make a graphical analysis of performance or to test your server/script/object behavior under heavy concurrent load.

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There are a few nice sites out there for testing, if you are looking for a web service for load testing. To name a few... (Paid service) (free up to 50 virtual users) ( free basic account)

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You can try siege, very simple and powerfull tool. By the way check limit of clients in apache.conf, look for "MaxClients" parameter.

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For openSUSE, it is available via the Benchmark community repository – bwDraco Sep 29 '13 at 4:47

You can use the curl library for stress testing.

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How would you do that ? – Iain Aug 9 '11 at 6:13
Using CURL you can programmatically create heavy load and induce Race conditions as well. There might be other tools as well, if you are totally new to CURL, you might as well learn a newer framework. Go through this link as a starting point… – Geek Aug 9 '11 at 6:22
I can understand the DOWN Vote but there are things you can ONLY do with CURL which other UI testing frameworks dont provide. – Geek Aug 9 '11 at 7:44
I'll give you a +1 to counter the slight unfair -1. Yes, you can write your own testing library with libcurl, but it's probably quite a effort given the readily available tools which do the job already. – Coops Aug 9 '11 at 8:39
An example of how to do it would would help. – Iain Aug 9 '11 at 12:41

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