Brad with a post on scaling LJ. I spoke w/ Brad one night about some of this stuff at this past SXSW (he has a sweet deal w/ F5), but it’s good to see where they’re going (see memcache info from lj_dev).
A few intersting notes. Brad mentions the uselessness of pconnects for MySQL, (yes) but goes on to blast InnoDB. From my experience, InnoDB is not only technically superior, but faster speedwise as well (some InnoDB vs MyISAM benchmarks). Also, although improvements have been made, MyISAM still has fugly row-level locking. The main real caveat is that there’s no full text search support current in InnoDB (others: slow counts due to multiversioning, auto-incrementing and table status are funky and other misc ‘stuff’).