Feature Request: Stored CRC

[raywood]

When I do a comparison of two drives, BC3 appears to recalculate everything from scratch. With a lot of files, this takes a looooonng time. In most cases, it also seems unnecessary, as very little has changed.

It would help if BC3 gave me an option of saving the results of a previous CRC comparison on my drive. Then, when I did a new comparison, it could start with folder size, subfolder size, and finally file size, to identify those places where there appeared to be a change, and could do a quick CRC just in those places. Basically, I want to click and have a more or less instant response, highlighting folders where there appear to have been changes, and then working ahead to clarify precisely where and what they were.

Sorry if there's a solution to this that I haven't come across or understood within the BC3 menus.

[snidely.too]

My first thought is snapshots, but I'm firing from the hip and may answer differently later.

/dps

[Aaron]

Hello,

BC3 has an option similar to this in the Folder Compare's session settings, Comparison tab. Enable Size and Timestamp comparison, also enable CRC comparison, and Override Quick Test Results.
The final option to enable is "Skip if quick tests indicate the files are the same"

This will run a filesize/timestamp comparison first, and if it finds a difference, it will generate a CRC code for only those files.

Snapshots can also store a CRC, but load as a virtual folder, so depending on what you want to compare (a folder to itself?) they may not be as useful for you.

[raywood]

Slowness, Linux Version, Compressed Drive

Those are the settings I'm using. Takes forever. It doesn't seem to make much difference whether I use binary or CRC.

It has occurred to me that maybe some of the problem is that I'm using the Linux version to copy over to an NTFS compressed USB-linked external drive. I don't have one that's not compressed, right now, to test with.

[Aaron]

Hello,

If those are your current settings, does that mean that when you compare, either the timestamps or size are always different? If so, which is inconsistent? If it is timestamp, you could try disabling that test or testing the Touch command to see if you can set the timestamps to be equal if the CRC is equal.