n 1 The duration of one tick of the system clock on your computer (see tick) Often one AC cycle time (1/60 second in the U S and Canada, 1/50 most other places), but more recently 1/100 sec has become common "The swapper runs every 6 jiffies" means that the virtual memory management routine is executed once for every 6 ticks of the clock, or about ten times a second 2 Confusingly, the term is sometimes also used for a 1-millisecond wall time interval 3 Even more confusingly, physicists semi-jokingly use `jiffy' to mean the time required for light to travel one foot in a vacuum, which turns out to be close to one nanosecond 4 Indeterminate time from a few seconds to forever "I'll do it in a jiffy" means certainly not now and possibly never This is a bit contrary to the more widespread use of the word Oppose nano See also Real Soon Now
n 1 The duration of one tick of the system clock on the computer (see {tick}) Often one AC cycle time (1/60 second in the U S and Canada, 1/50 most other places), but more recently 1/100 sec has become common "The swapper runs every 6 jiffies" means that the virtual memory management routine is executed once for every 6 ticks of the clock, or about ten times a second 2 Confusingly, the term is sometimes also used for a 1-millisecond {wall time} interval Even more confusingly, physicists semi-jokingly use `jiffy' to mean the time required for light to travel one foot in a vacuum, which turns out to be close to one *nanosecond* 3 Indeterminate time from a few seconds to forever "I'll do it in a jiffy" means certainly not now and possibly never This is a bit contrary to the more widespread use of the word Oppose {nano} See also {Real Soon Now}
Basic packet of kernel time, around 10ms on x86 Related to HZ, the basic resolution of the operating system The timer interrupt is raised each 10ms, which then performs some h/w timer related stuff, and marks a couple of bh's ready to run if applicable