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March 2, 2009
A SysAdmin's Guide to Users
I think we're all guilty of retribution at some point in our lives, even if we're not proud of it. I'd be lying if I said that I didn't implement firewall rules at an ISP in direct response to user activity. The user didn't break the terms of service (TOS) in literal word, but in spirit, and I reacted to that by changing the firewall rules specifically to prevent them from doing what they were doing. What I should have done was discuss the situation with management, edit the TOS, and the firewall to reflect it. Fortunately in my job roles after that, I have reacted more maturely to issues such as these.
http://www.simple-talk.com/exchange/exchange-articles/a-sysadmins-guide-to-users/
Posted by thdyck at March 2, 2009 | Comments (0) | TrackBack
Wikipedia: site internals, etc (the workbook) « domas mituzas: vaporware, inc.
There still are details (and even complete subsystems) to be documented more thoroughly, but this is the workbook I presented at MySQL Conference. I've heard comments that the book has 'hypothetical' situations, but generally every bit is there represents real practice we're having.
The talk did drift to some bits of information that may not be there (or did go much deeper), as well as the book covers some parts of operations that were not discussed at the tutorial talk. Anyway, I hope both session and tutorial has some value.
Here's the file: Wikipedia: Site internals, configuration, code examples and management issues (the workbook). For now it is PDF, but I hope to transform it into properly evolving public document.
Update: Another good presentation on Wikipedia technology by Mark: Wikimedia Architecture
Wikipedia: site internals, etc (the workbook)
Posted by thdyck at March 2, 2009 | Comments (0) | TrackBack
Microsoft TechNet: Using Transaction Cost Analysis for Site Capacity Planning
TCA methodology can be used to measure the cost of individual shopper operations, such as registering on the site, browsing, searching, adding an item to the shopping cart, checking out, and so on. You determine the capacity of a site by dividing the costs of shopper operations into the total resources available from the server. To simplify the discussion of TCA methodology, this white paper focuses on determining the CPU capacity of the server only. For a discussion of calculating multiple resource costs on the server, see the Capacity Model for Internet Transactions white paper, available from the same Web page as this white paper.
After you understand the cost and relative frequency of each shopper operation, you can view the performance numbers for a site's pages to identify where the bottlenecks are, and identify where you can optimize performance to improve the site's capacity.
For example, TCA methodology can help you determine which operations are the most costly, which pages are accessed most frequently, and so on. You can use the performance data that you collect, using TCA methodology, to perform "what if" scenarios. This way you can see how performance improvements (or degradation) affect your site. Once you know the cost of each operation, you can improve the performance of your site by optimizing high cost or frequently used Web pages. If you need additional capacity, identifying and lowering the cost of these "expensive Web pages" will help. In addition, you will clearly see the impact of adding features to a Web page, and can plan to install additional hardware required to service the load generated by additional shoppers or new code releases.
A Transaction Cost Analysis is comprised of the following:
* Compile a User Profile
* Measure the Cost of Each Operation
* Estimate Site Capacity
* Calculate Site Capacity
* Verify Site Capacity
http://technet.microsoft.com/en-us/commerceserver/bb608757.aspx
Posted by thdyck at March 2, 2009 | Comments (0) | TrackBack