The sys admin's daily grind – httpstat

My Point of View

Article from Issue 195/2017

Httpstat is a special stopwatch you can use to discover how long web servers take to serve up a static or dynamic HTML page. Visible performance lags indicate optimization potential for the server.

Httpstat is a Python script that wraps itself around cURL. Apart from Python 2 or 3 and cURL, it has no other dependencies. You can retrieve it from the GitHub repository and call it using:

python <URL>

If the Python installer pip is present on your system, you also can pick up the script and call it with:

pip install httpstat
httpstat <URL>

Although you can leave an http:// out of the URL, you cannot omit https:// for web pages secured with TLS.

Figure 1 shows httpstat measuring an unencrypted call. Four milliseconds for a DNS reply is a really good value, but I cheated: The name of the site is cached on my local Dnsmasq. As soon as my computer has to turn to my provider's DNS, the value rises to 80-200ms. The TCP handshake is 22ms, which is about par for the course.

Figure 1: The page that httpstat requests via HTTP, and receives quickly, is only an error message in reality.

The time the server needs to create the page (Server Processing) shows whether the web server has some tuning potential that I have not tapped. My example is not representative, because instead of HTML, the server simply outputs 301 Moved Permanently, which means I should have called the page using HTTPS. A browser would do that independently, but not cURL.

Figure 2 requests the same page using HTTPS. The lookup and TCP values remain the same, but the TLS Handshake takes forever for this static page. The value can go up to several seconds for a big site with a large volume of dynamic content and advertising banners.

Figure 2: When requested using HTTPS, the HTML page obviously takes longer to appear.

Httpstat is not controllable using command-line parameters because they would be fielded by cURL; however, you can influence the tool with environment variables. The line


tells httpstat to show how quickly the web page is delivered (e.g., speed_download: 219.6 KiB/s, speed_upload: 0.0 KiB/s). The httpstat website [1] explains all of the variables and has links to the httpstat implementation in Go, Bash, and PHP.

The Author

Charly Kühnast manages Unix systems in the data center in the Lower Rhine region of Germany. His responsibilities include ensuring the security and availability of firewalls and the DMZ.

Buy this article as PDF

Express-Checkout as PDF
Price $2.95
(incl. VAT)

Buy Linux Magazine

Get it on Google Play

US / Canada

Get it on Google Play

UK / Australia

Related content

  • The sys admin's daily grind: Smorgasbord

    Sys admin columnist Charly Kühnast has an electronic note box in which he collects ideas and small snippets of code. He calls it his "quarry" and is taking this opportunity to offer up some collectors' items to regular readers.

  • Highway Through Hell

    When digging into BGP routing information, Charly avoids the highway through parameter hell thanks to the ASN tool. In addition to a system's AS number, ASN delivers other information, such as its peering partners upstream and downstream.

  • The sys admin's daily grind: Rclone

    Having a good backup is a matter of course for sys admin columnist Charly Kühnast, but devices could still fall victim to fire or theft some day. Because he has enough free space on Google Drive, he doesn't need to search long for a solution. The only thing missing is the right tool.

  • The sys admin’s daily grind: Sysdig

    In this issue, sys admin columnist and tool veterinarian Charly Kühnast invites Sysdig, the jack-of-all-trades among system diagnostic tools, into his surgery for a quick checkup. The project promises to unite the functionality of lsof, iftop, netstat, tcpdump, and others.

  • The sys admin's daily grind:

    Whenever you really need documentation, it's almost always incomplete or outdated – or both. Sys admin columnist Charly K¸hnast recommends a radically different approach: the universal community documentation, which no Linux command and hardly any programming language should do without.

comments powered by Disqus
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters

Support Our Work

Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

Learn More