"Scanning folders" stalls almost forever

[cstern]

I have some NAS drives, which are mounted via smb. When I want to make a folder compare and copy or move files from the local HDD to or from the NAS it can take a huge amount of time before something happens. BC4 says "Scanning folders". Even if I force open all sub folders, it will insist on (apparantly) looking at each and every file before doing anything. This is really annoying.
Example: I have my photo archive on the NAS. I have transferred new pictures from my camera to my mac and want to place the edited pictures on my NAS. I open BC4 and have the local HDD on one side and the NAS on the other. On the NAS I have pictures from when I started taking them - that means many many thousands, in hundreds of folders.
So, if I want to transfer the most recent ones (e.g. a new folder called "Claus' birthday 2018") to the NAS it will take 20-30 minutes after I ask BC4 to copy the folder to the NAS. Argh! That is really annoying.

WHY does this happen - and HOW can I circumvent this?

Thanks for your assistance.

PS: This has been a problem always...

[daviso]

I'm having the same/a similar problem.

[cstern]

This morning: Wanted to copy five directories to the NAS:

"Scanning folders: Waiting" has been shown in FC for the last 10 minutes...

[Aaron]

Hello,

If you set a completely empty base folder on the NAS side of the compare, does it take similarly long to begin the transfer for a small data set? How many files/folders are in your five directories?

Are you using the latest release of BC4 (4.2.6)? Which platform are you running on?

[cstern]

I have tried an empty folder - that works fine.

Here's a setup that doesn't work:

LHS: NAS share mounted on "Photos". The share has a folder with the name CanonPhotos which contains maybe 1000 folders, each with from 10 - 1000 files, some with subfolders
RHS: a local folder ~/Documents/NewPhotos, with a folder also called CanonPhotos, containing one folder ("OldPhotos") which has been copied to the NAS (all identical files), and one with new files, but in a folder which name already exists on the NAS ("NewOnes").

BC folder compare of the two ("CanonPhotos" exists on both sides): It is shown that the folder with the identical files is - identical. I wish to delete that folder on the mac because it is already copied to the NAS. So, I select the folder ("OldPhotos") on the RHS and select "Delete" from the right-click menu. Here is where the strange thing happens: BC wants to scan each and every folder (or maybe only in the CanonPhotos folder) on the NAS side before the mac side folder is deleted. Same thing happens if I want to copy or move the new files in the folder "NewOnes" to the NAS.

With these many folders and files on the NAS it can take from minutes to literally hours before the scanning is done. If I copy the folder with the new files using the command line the copying is done almost instantanously (maybe a delay of a couple of seconds).

The OS is High Sierra 10.13.6, the NAS is a WesternDigital MyCloud 4TB.

LHS:
-Share (mounted as "Photos")
--Subfolder (among several others) CanonPhotos
---Many subfolders (one of is "OldPhotos", another "NewOnes")

RHS:
~/Documents/NewPhotos
--Subfolder CanonPhotos
---Subfolder OldPhotos
---Subfolder NewOnes

[Aaron]

Hello,

Ok, have you also limited the initial folder building/scanning in the Handling tab of the Session Settings?

If before acting you issue an Expand All command, wait for the full building to complete, and then issue your command, what behavior do you see? How long does the initial build take compared to the command?

When working with the command line or Explorer, these programs only need to interact with the immediate level. BC4, however, is a comparison utility showing both how the current level compares side by side, and also how it contributes to the built levels above it (that's how the comparison status and coloring is calculated). For large base folders, this can be much more intensive since BC4 is looking at multiple levels and both sides (to build the comparison) while the command line/Explorer is very limited in scope.