Failed requests by length in my ApacheBench load test result

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Stack Overflow for Teams Where developers & technologists share private knowledge with coworkers , Stack Overflow help chat ,Run ab with the -v 2 parameter, meaning verbosity level 2. This will dump the response headers. If your requests are not using chunked encoding, you will see a "Content-Length" header indicating the size of each response.,Thanks for contributing an answer to Stack Overflow!

Run ab with the -v 2 parameter, meaning verbosity level 2. This will dump the response headers. If your requests are not using chunked encoding, you will see a "Content-Length" header indicating the size of each response.

gw: ~$ ab - n 1 - v 2 "http://whatever.com/"

   ...

   LOG: header received:
   HTTP / 1.0 200 OK
   ...
   Content - Length: 1568399
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Nevermind. The "length failure" merely indicates that about half the time the length of the response was different.,Since the contents are dynamic, it's probably the session identifier or something like that.,The apache benchmarking tool (ab) assumes that length of response content will be the same during entire test. It stores the content length of the first response. If any of further responses have different content length, they result in "length failures".,Summary: If you are serving any content of variable length, you should probably ignore this kind of ab request failures.

Edit: I have recently noticed that the ab command has a new (at least for me) option:

-l Accept variable document length(use this
   for dynamic pages)
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Request latency metrics,endwrite: when ab finished writing the request,If you set a -c value greater than 1, the second Time per request metric should (in theory) provide a more accurate assessment of how long each request takes.,From there, use the higher-granularity aggregated connection times to find out which part(s) of the request-response cycle to investigate further.

apt - get update
apt - get install - y apache2 - utils
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Load Testing with AB … fake failed requests (length),While benchmarking the site, try to see how many connections are established in port 80:,Repeat this command a couple of times while benchmarking the site. Probably you'll be hitting 50 established connections.,Connect and share knowledge within a single location that is structured and easy to search.

While benchmarking the site, try to see how many connections are established in port 80:

netstat - tnap | grep ":80" | grep - c ESTA
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As I mentioned, you can also use Apache Bench to run other types of tests under the “Performance Testing” umbrella.,If you want to learn more about Okta and software development in general, check out some of our other awesome content!,If you have access to a Mac or Linux system, chances are you already have Apache Bench installed as a program called ab. Run a simple load test with:,The last block is pretty self-explanatory. It breaks down the requests by time, letting you know that 50% of the requests finished in 148 milliseconds, 66% were done by 225 milliseconds, and so on down to the longest request time of 993 milliseconds.

ab - n 100 - c 10 https: //google.com/
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When you use ab to do some performance benchmarking, you might run into output like this:,Note that in our example these "Failed requests" actually never failed.\ For some requests, the application just returned a response with a different content length than the first response. This is indicated by the "Length: 5" bit in the example above.,If you see requests that failed with other kinds of errors, they probably failed for real., By refactoring problematic code and creating automated tests, makandra can vastly improve the maintainability of your Rails application.

When you use ab to do some performance benchmarking, you might run into output like this:

CopyComplete requests: 200
Failed requests: 5(Connect: 0, Receive: 0, Length: 5, Exceptions: 0)
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There are various statically declared buffers of fixed length. Combined with the lazy parsing of the command line arguments, the response headers from the server and other external inputs, this might bite you.,The following list describes the values returned by ab: ,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.,Copyright 2021 The Apache Software Foundation.Licensed under the Apache License, Version 2.0.

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.

ab
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Requests per second − This is the number of requests per second. This value is the result of dividing the number of requests by the total time taken.,Apache Bench - Quick Guide,Concurrency level should be lower than the total number of requests.,Concurrency Level − This is the number of concurrent clients (equivalent to web browsers) used during the test.

Step 1 − Update package database.

# apt - get update
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In the above output, Apache will display key metrics such as Time taken for tests, No. of requests completed, Failed requests, Total data transferred, HTML transferred, Requests per second, Time Per Request, Transfer rate.,After Apache bench runs the tests, it will produce an output like the following.,Here are the steps to install and use Apache bench for load testing.,Hopefully, this article will help you set up and run load testing for Apache web server. Ubiq makes it easy to visualize data, and monitor them in real-time dashboards. Try Ubiq for free.

Ubuntu/Debian

$ sudo apt - get update
$ sudo apt - get install - y apache2 - utils
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3 How to Use Apache Bench for Load Testing? , 10 Apache Bench Usage Example for Google Load Test , 9 Apache Bench Usage Example for Twitter Load Test , 8 Apache Bench Usage Example for Facebook Load Test

To download the Apache Benchmark with “apt-get” command, you can use the example below.

apt - get install apache2 - utils
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