Thoughts and Ramblings

General things I find of interest.

Trac.fcgi Memory Usage

I’ve been slowly transitioning to using nginx as the web front-end in an effort to reduce Apache’s memory usage. In keeping with this task, I’m moving more and more off of Apache. One piece I recently moved was trac, transitioning to using it directly by nginx by running it in fast-cgi mode where as previously it was running as cgi though Apache.

While fast-cgi is faster, it has inherent issues, such as any memory leak can result in ever growing memory usage, which is exactly why Apache has a setting for each child to serve a limited number of requests before exiting. Trac.fcgi has no such directive, and has the equivalent of a large memory leak, a non-expiring cache. While it’s not as bad as a memory leak, which will indefinitely grow instead of reaching a limit, if the cache size is larger than the available memory for trac to use, it’s just as serious. The only solution, without fixing trac’s caching mechanisms, is to restart trac periodically, but during the time trac is restarting, all requests are lost, causing bad gateway errors to the user. Additionally, the restart needs to be done manually. Clearly not an ideal solution.


Google Link Redirection (cont.)

Earlier I wrote about google’s link redirection. I have finally finished my testing of a Safari extension which kills this behavior. I didn’t want to release this extension until the updating mechanism worked and that is what took me so long. Anyway, here is the the extension. Enjoy, and let me know what you think.


Why you shouldn't buy A Flip Camera

So, my parents were using a Flip Ultra HD to record sermons. This camera has a serious flaw which the company has acknowledged and failed to fix. First, the camera has 8GB of memory which it formats into a FAT-32 filesystem. This filesystem has a well known limitation where it cannot have a file which exceeds 4GB in size. The Flip camera, when recoding in HD, will hit this limitation in about an hour (depending on the motion in the video). The simple solution to this is to simply split the recording into multiple files so as to not cause any issues. Pure Digital Technologies, Inc, unlike their competitors, doesn’t seem to have figured out this simple solution but instead elected to have the camera beep and turn itself off. This completely violates what a consumer would expect out of a camera in that it will continually record until it is out of power or out of memory, or in the old days, tape.


Google’s Link Redirection

Google, for quite some time, has been redirected clicks on links in their search results to www.google.com/url?…. While I don’t approve of such practices, I didn’t mind it so much since this is presumably an effort to improve their search results. That changed recently, when I noticed that my history in Safari was filled with entries containing that URL as the title. Considering the fact that I often use the history to re-find a page with pertinent information, this is bordering on making my browser usage useless. Note: I tend to cmd-click links so they show up in new tabs. If you just click the link, the title in the history is correct.


Text Compression Code Released

After it’s original post, I got a request for the code I used in my text compression technique. I’ve not gotten around to cleaning up the code and separating it from it’s test environment so it can be distributed separately. You can read more about it in its own page.

Sometime soon, I’ll get around to releasing my code for fetching old Escape Pod episodes that I hinted at earlier.