Backup and sync software: MD5 = overkill?

fredhammersmith333

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May 7, 2009
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Hi. The recent lost of many important professional files (pictures) made me want to switch backup and sync application.

I am very interested in GoodSync, which seems to be automatically monitoring moved files and folders, which is something that could be very helpful to me (the fact that I have to move files a lot may be the one thing that made me lose some of them).

But, paranoid as I am, i turned on the MD5 switch, makinbg the process very very slow. My previous backup software had a CRC check as well: it was way quicker though.

Is MD5 examination overkill? In fact, since I am involved a lot in data duplication (digital film), I always ask for CRC check of some kind on work. But is it really necessary?

I am using three Windows 7 64-bit and Windows 8 computers in a home network.
 
Solution
Both CRC and MD5 calculate checksums, and can get even a single bit (or byte swap) of the data. I don't know why MD5 slows down your backup process, it should be not much slower than CRC.

Edit: Just did some timing. On my old xps210 desktop (Core2Duo, run-of-the-mill SATA drive) both CRC32 and MD5SUM finished in roughly the same time, checksumming 4gb file for a minute.

Spectre694

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Feb 28, 2014
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CRC simply checks if data is changed as it is transferred between devices dropped corrupted packets and the like.
MD5 is a checksum and checks the entire file for any changes from the original file both when writing to the backup and then later writing back to the original.

You will have to decide if that extra check is worth it checksumming is very CPU intensive which is why it has slowed sown it has to calculate it for each file before transferring.

 
Both CRC and MD5 calculate checksums, and can get even a single bit (or byte swap) of the data. I don't know why MD5 slows down your backup process, it should be not much slower than CRC.

Edit: Just did some timing. On my old xps210 desktop (Core2Duo, run-of-the-mill SATA drive) both CRC32 and MD5SUM finished in roughly the same time, checksumming 4gb file for a minute.
 
Solution

Spectre694

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Feb 28, 2014
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Not that I know of. It is pretty good about not corrupting files but it does do it once in a while it is rare though.