Year 2042
On 17 September 2042, at 23:53:57.370496 TAI, the Time of Day Clock on S/370 IBM mainframe and its successors, including the current zSeries, will roll over. The UTC time will be a few seconds earlier, due to leap seconds.
The TOD Clock is implemented as a 64-bit count of 2−12 microsecond (0.244 ns) units, and the standard base is 1 January 1900. The actual resolution depends on the model, but the format is consistent, and will therefore roll over after 252 microseconds. Note that IBM time base is exactly 10 seconds off TAI (it was originally defined in UTC, when that was the offset from TAI).
The TOD Clock value is accessible to user mode programs, and is often used for timing and for generating unique IDs for events.
While IBM has defined and implemented a longer (128-bit) hardware format on recent machines, which extends the timer on both ends, many programs continue to rely on the 64-bit format which remains as an accessible subset of the longer timer.
Read more about this topic: Time Formatting And Storage Bugs
Famous quotes containing the word year:
“For Afro-Americans, it could be argued that every year they’ve spent in this country since they arrived in chains to perform forced labor has been 1984.”
—Ishmael Reed (b. 1938)