was designed to be forward looking only, make the most of lower spec machines, and not scale to massive hardware. ie [sic] it is a desktop orientated scheduler, with extremely low latencies for excellent interactivity by design rather than "calculated", with rigid fairness, nice priority distribution and extreme scalability within normal load levels.
The bug we are talking about is the infamous switchboard timeout error which was very elusive, it happened randomly, and very often for some users in unknown conditions. Essentially you send a message, and after one minute you receive a notification telling you the message never arrived, after which you need to resend the message, and hope it will arrive this time.
"A complex system that works is invariably found to have evolved from a simple system that worked." -- John Gall, _Systemantics_