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Measuring website latency with http_ping
A year or so ago, I modified my ldap-ping.pl script to create a script (http-ping.p l) that would measure the time it took to retrieve a specific URI from a web server. While scouring the OpenBSD ports collection for website monitoring tools, I came across http_ping. This is a great tool for measuring the time it takes to retrieve a URI, and is a far superior tool to the one I wrote. Here is an example of http_ping in action: There are all kinds of nifty pieces of software stashed away in the OpenBSD ports collection, and I am on a mission to locate and blog about each and every one of them…
$ read more →Measuring website latency
While reading a slew of information on web application monitoring, I came across echoping. This nifty little utility allows you to measure the time it takes to ping a server, perform an SMTP exchange with a mail server, or to request a URI from a web server. The following example uses the echoping "-h" (URI to fetch) option to measure the time it takes to request a URI from the prefetch.net web server: To measure the time it takes to complete an SMTP transaction with mail.prefetch.net, smokeping's "-S" (perform SMTP exchange) option can be used: echoping supports TLS and SSL, and the data generated by echoping can be graphed with cacti or smokeping.
$ read more →Measuring packet loss
In continuing on with my commitment to describe my favorite network utilities, I bring to you mtr: mtr allows you to view hop-by-hop latency metrics, and is invaluable for finding busy devices between two endpoints. Some routers will place low QOS priorities on ICMP traffic, so it is important to capture traffic at various intervals to see if a device is truly overloaded.
$ read more →Siege web benchmarking utility
While I am waiting for Apache to build with the libtool --debug option, I thought I would share my thoughts on the siege utility. Siege is an open source HTTP regression and debugging utility. I have used curl and ab in the past to debug and benchmark websites, but prefer siege, since it allows me to debug and benchmark websites with a single well written utility. To debug the HTTP requests to a server, you can run run siege with the "-g" (Grab headers) and "-u" (URL to grab) option: This displays a summary of the request/entity headers for the entire HTTP transaction, and is super useful for debugging…
$ read more →Measuring Website Page Load Times
I was curious to see how long it would take to load "index.html" from my web server, so I created http-ping.pl to measure the time it took to retrieve a webpage from my web server: This will display the time it takes to perform the TCP three way handshake ( Syn, Syn/Ack, Ack), and GET the index page from a web server. This was a quick and dirty hack, and a full rewrite in C (w/ SSL support and timings!) is forthcoming.
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