I came across recently, as you do, an option to maximise the performance of my lowly OCZ Core V2 SSD in Ubuntu. Apparently the kernel goes to quite extreme lengths (in terms of using CPU cycles) to avoid doing seeks. With a “standard” hard drive this is desirable because the time it takes the head to move to the correct location is more costly. Seeking is irrelevant as far as an SSD is concerned and using extra CPU time only serves to reduce I/O performance. Happily there is an option to tell the kernel that you are using a non-rotational media for a specific drive designation i.e. sda, sdb, etc. and therefore maximise SSD performance.
Just a quick one today. It seems to be a recurring problem for me that every once in a while I want to go into Amavisd-new’s quarantine and look for false positives (not that there should be any if it’s setup right). There are a number or graphical ways of doing this but most of them aren’t available in the Ubuntu repositories. The 2 that I could find are Horde-sam and Webmin’s Clamav module (which I have used before and is pretty easy to use if you are command-line averse). I didn’t want to add another service in order to keep resource usage as low as possible so I set about finding a way to check each email from the command line. So firstly to cycle through every quarantined email use the following command in the quarantine directory (normally /var/lib/amavis/virusmails in Ubuntu):-