Tag Archives: iis

A powershell script for running reverse lookups on many IP addresses at once

I often find myself looking at web logs when researching anomalous traffic on our servers.  It’s not uncommon for a poorly written web scraper to come through the system and generate spurious errors, and I start looking at what IP … Continue reading

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Performance: generate web traffic load using a powershell script

The other day, I found myself wanting a quick and dirty way to throw a controlled amount of load against a server for the purpose of tuning some thread settings.  What I wanted was to simulate varying numbers of concurrent … Continue reading

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Debugging: Use Fiddler and WebProxy to debug HttpWebRequest / HttpWebResponse issues in ASP.NET

We recently found ourselves debugging code that was making web requests to another server.  If we hit the server manually in a web browser, it worked fine, but when we ran it through the code simulating the request using HttpWebRequest, … Continue reading

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Performance: Yes, time-taken in IIS includes network time

I’ve written previously about many of the useful types of analysis you can perform using the time-taken field in your web logs.  However, I would be remiss for not pointing out some limitations of the data it provides. When poring … Continue reading

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Solved: ASP.NET Web Services using POST only work on localhost by default

This information isn’t exactly secret, but it took a bit of googling around to piece the answer together, so I wanted to share it in a more condensed form.   We are in the process of migrating some legacy ASP … Continue reading

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Kick off a Cygwin script from a windows bat file with a different working directory

I recently created a script that would pull the Tomcat log files from a group of web servers and then run my 95th percentile awk script to generate a summary of response times for the 100 most popular pages.  I … Continue reading

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Performance: Hyper-threading actually does boost server capacity

We recently noticed some odd behavior with one of our servers during a deployment.  Several machines were removed from the traffic pool to receive updates, and during this time, the other machines were shouldering the extra load.  We have significant … Continue reading

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Performance: An awk script for computing 95th percentile times straight from web log files (IIS, Tomcat)

When analyzing performance, looking at 95th percentile response times is one of the most useful metrics.  While the average can be a good indicator, it can be heavily skewed by lots of small requests or a few extremely long ones.  … Continue reading

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Performance Tuning: Visualize your web log performance data using Excel scatter plots

I’ve written previously about how to turn on time-taken values in web logs for IIS, Tomcat, and Apache.  Armed with time-taken data, you can identify which are the slow pages in your system and decide where to focus your performance … Continue reading

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Performance Tuning Tip: Turn on time-taken in your web logs (IIS, Apache, Tomcat) to identify performance hot spots

Everyone knows that the web logs generated by web servers like IIS, Apache, and Tomcat (JBOSS / Catalina) are a well-known goldmine of information.  They allow you to track site usage, find content errors, gather browser statistics, and all sorts … Continue reading

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