Archive for June, 2009
cinfo for seeing how much of a file is being cached
cinfo is a kick ass program written by the author of PowerDNS Bert Hubert to show how much of a file is being cached by the operating system. It’s great for testing to see if myisam data files are being read from the operating system cache or off disk. For example this is the cache [...]
Load average
Modern operating systems give the impression of running more processes than the number of available processors by giving each process that wants to run, such as your web browser or text editor a tiny slice of time in which they can execute. By switching out the running process very quickly it looks as though all [...]
fadvise syscall, myisam data file caching, and a lesson learned in debugging
fadvise is a system call that can be used to give Linux hints about how it should be caching files. It has a few options for caching, not caching, read ahead, and random access. I was looking into used fadvise because a client ran into an issue where some infrequently used myisam data files were [...]
Using vim as a man page viewer
I love color on my terminal. Black and white editors and and man pages are boring and more difficult to read than simple syntax highlighting. Vim supports syntax highlighting for man pages. Using it is as simple as setting an environment variable.
MANPAGER=”col -b | vim -c ’set ft=man nomod nolist’ -”
You can add this line [...]