| Pebioctets per second (Pio/s) | Zebibits per second (Zibit/s) |
|---|---|
| 1 Pebioctet per second | 0.00000762939453125 Zibit/s |
| 2 Pebioctets per second | 0.0000152587890625 Zibit/s |
| 3 Pebioctets per second | 0.0000228881835938 Zibit/s |
| 4 Pebioctets per second | 0.000030517578125 Zibit/s |
| 5 Pebioctets per second | 0.0000381469726562 Zibit/s |
| 10 Pebioctets per second | 0.0000762939453125 Zibit/s |
| 20 Pebioctets per second | 0.000152587890625 Zibit/s |
| 25 Pebioctets per second | 0.000190734863281 Zibit/s |
| 50 Pebioctets per second | 0.000381469726562 Zibit/s |
| 100 Pebioctets per second | 0.000762939453125 Zibit/s |
| Reference | Pebioctets per second (Pio/s) | Zebibits per second (Zibit/s) |
|---|---|---|
| A dial-up modem | 6.21725 × 10-12 Pio/s | 4.74338 × 10-17 Zibit/s |
| Typical home broadband | 0.0000000111022 Pio/s | 8.47033 × 10-14 Zibit/s |
| Gigabit Ethernet | 0.000000111022 Pio/s | 8.47033 × 10-13 Zibit/s |
| Streaming a 4K film | 0.00000000277556 Pio/s | 2.11758 × 10-14 Zibit/s |
The pebioctet per second is a unit of data transfer rate equal to 1,024 tebioctets per second, or two to the fiftieth power octets per second. Its symbol is Pio/s. It is the binary counterpart of the petaoctet per second, and the two differ by 12.6 per cent.
The rate exists only as a total. The aggregate memory bandwidth of a whole supercomputer, or the summed capacity of the network fabric joining its cabinets, reaches this range, and both are sums over tens of thousands of components, each of which moves a few hundred gibioctets per second on its own.
Whether such a total means anything depends on the calculation being run. A problem that divides so that each node works mostly on its own data can use the full aggregate. A problem where every node must constantly consult every other cannot, and the machine's effective bandwidth falls to what the slowest shared path allows. Most of the art of parallel programming lies in getting problems into the first category.
In octets a pebioctet per second is 1,125,899,906,842,624, and in decimal terms about 1.126 petaoctets per second. The 12.6 per cent difference is the accumulated effect of five multiplications by 1.024, and it is now large enough that no report can leave the convention unstated without introducing real uncertainty.
The unit also appears in descriptions of parallel filesystems at the largest facilities, where a storage system spread across tens of thousands of drives delivers a few pebioctets per second to a compute cluster. That number determines how quickly the machine can checkpoint its state, which in turn determines how much work is lost when a component fails — and in a machine of that size, something is always failing.
For a converter the requirement is simply that the arithmetic be exact and the label preserved. Multiplying by 1,024 five times is not difficult; silently substituting the decimal prefix is the error to avoid.
One pebioctet per second equals 1,024 tebioctets per second, 1,125,899,906,842,624 octets per second, or about 1.126 petaoctets per second.
The zebibit per second is a unit of data transfer rate equal to two to the seventieth power bits per second, which is 1,024 exbibits per second. Its symbol is Zibit/s. It is the binary counterpart of the zettabit per second, and the two differ by 18.1 per cent — approaching a fifth.
Nothing runs at this rate, and nothing is designed to. A zebibit per second is about a thousand times the total instantaneous traffic of the internet, and it would move the world's entire stock of stored data in a matter of minutes. The unit exists because the IEC series, like the metric series it parallels, was defined completely rather than only as far as anyone then needed.
That completeness is a deliberate design principle rather than an oversight. A measurement system whose names run out at some arbitrary point forces every future user to improvise an extension, and improvised extensions conflict with one another. Defining the whole ladder in advance costs nothing and removes the possibility.
The eighteen per cent gap at this level is the clearest illustration of why the binary series was needed at all. At the kibibit the two conventions differed by 2.4 per cent, which nobody noticed; the discrepancy multiplies by 1.024 at each step, and by here it is large enough that no reader could treat the two labels as interchangeable even in casual writing.
In octets a zebibit per second is 147,573,952,589,676,412,928, or 128 exbioctets per second. Expressing the same rate in every unit on the scale is an exercise rather than an application, but it is one a converter has to perform correctly, because the arithmetic does not become approximate when the quantity becomes unreachable.
The practical lesson is the one the whole binary series teaches: the lowercase i is not optional. It is the only mark in a written figure that distinguishes a power of two from a power of ten, and by this point in the scale the two are nearly a fifth apart.
One zebibit per second equals 1,024 exbibits per second, 147,573,952,589,676,412,928 octets per second, or about 1.181 zettabits per second.