Mebibyte (MiB) instead of Megabyte in Log

[ryan5...@gmail.com]

Hello Hiroaki,

Your FastCopy program is the BEST in its class, I have been using FastCopy for over 10 years.  Thank you.

This question has been bugging me for a long time - "Why do you use Mebibyte (MiB) instead of Megabyte (MB) in your Log file?".
Is it possible to change it to Megabyte (MB) please in the next version. (No one understand what Mebibyte (MIB) is)

I am very surprised that no one has asked this question before.

Best regards,
Ryan

[Dan Alexandru]

I was going to ask the opposite, that the author replace more occurrences of “MB” to “MiB” (e.g. in Buffer), to be both consistent and more technically accurate.

[ryan5...@gmail.com]

We are using FastCopy to copy data from one storage media to another such as Hard Disks, USB Drives/Sticks etc. I have not seen a single storage media in this planet that comes in "MiB" or "GiB" or "TiB", they only come in "MB", "GB" or "TB".  So when you transfer data from such storage media to another, we do NOT need to know the amount of data it transfered in (MiB) or the rate in which it transfered the data in (MiB/s).  Because we cannot relate those values (units) to the actual storage media size.

For example, we never call a 64GB USB Stick a 59.6GiB USB Stick just because you want to be more technical or accurate.  If I have 20GB of data on that 64GB USB Stick and would want to transfer it using FastCopy to another media, I do not want FastCopy to convert the data amount unit from 20GB to 18.63GiB or the transfer rate in MiB/s instead of MB/s.  To be technically accurate would you say "I had 236.588ml of tea" instead of saying "I had a cup of tea"?.

[Hiroaki SHIROUZU]

I can understand that your feelings, but I have thought I have to change the notation.

If KB/MB/GB/TB notation is used, the number becomes greater than KiB/MiB/GiB/TiB notation.

So Storage vender like MB notation than MiB for publicity. (1TB is 0.9TiB)

But Windows MB notation (and old FastCopy MB notation) doesn't mean MB(10^6).

It is calculated MiB(2^20), but notation is MB.

(format size, file size, transfer rate, or all numbers representing the file size in Windows Desktop)

But some tools shows MB notation that means 10^6. (CrystalDiskMark or etc)

If "FastCopy's MB means 2^20" isn't known, some people think "FastCopy is slow than CrystalDiskMark's bench, why?"

So I thought I should change MB to MiB.

[Dan Alexandru]

I think we are all in agreement on the basic facts:
- Manufacturers are reporting sizes in the decimal system (1 KB = 1,000 bytes; 1 GB = 1,000,000,000 bytes) mainly because their competition uses this to report higher numbers for disk capacities
- Apple has recently switched to reporting sizes in the decimal system (1 KB = 1,000 bytes; 1 GB = 1,000,000,000 bytes) mainly because [they can put users first](https://support.apple.com/en-us/HT201402)
- Microsoft is still reporting sizes in the JEDEC binary system (1 KB = 1,024 bytes; 1 GB = 1,073,741,824 bytes) mainly [because of inertia](http://blogs.msdn.com/b/oldnewthing/archive/2009/06/11/9725386.aspx); and they have to [explain the discrepancy every time](https://support.microsoft.com/en-us/help/2581408/windows-support-for-hard-disks-that-are-larger-than-2-tb)
- Professional tools are reporting sizes in the IEC binary system (1 KiB = 1,024 bytes; 1 GiB = 1,073,741,824 bytes) mainly because they need to be technically correct.

I would argue that FastCopy falls in that last category.

Switching to the IEC standard seems like a good idea to me, in order to be consistent with previous versions and similar tools (I would argue that CrystalDiskMark is an exception).