External Hard-Drive shows near-constant activity

It takes days-weeks for Photos to index such largish library (it does it when the Mac has been idling for a few minutes). I recently disabled sleep in my Mac and let it run all day and night (the display went off after 1-5 minutes idling) and it took a week for my similar library until photos had indexed it.

Make sure to store Photos library on APFS or MacOS Extended (GUID) case insensitive volume. exFAT and other non-Mac formats are not supported and might corrupt the library.

pdibello wrote:

That said, if this continued, after how long should I be concerned? A month?

With my almost similar sized library it took almost two weeks. I am not sure but after a week when I set the it as a system library, it seemed to take a finishing spurt.

I initially had the library on the Mac mini 2018 internal 1 TB disk so I did not notice the disk activity unless took a peek at the Activity Monitor and let the Mac idle for a few minutes. I have now moved the library to an external SSD to make room for other projects on the internal disk.

I have planned to bite the bullet and cough up some $$ and try iCloud Photos later because my 400 GB library does not fit to my 250 GB iPad Air so I sync only the most recent or oldest movies to it in addition to all images. And syncing is slow and sometimes it has been very flaky.

pdibello wrote:… I am using 4 SSDs in RAID 10 (Samsung 870 EVO)

In spite of my apparent guru status conferred on me by OT, I don't pay much attention to photoanalysisd and its cousins unless something's gone terribly wrong, and then not much. I prefer the "shrug and baskeball" approach.

I'm not at all sure how well Photos works with RAID systems. Photos Libraries seem very sensitive to timing interference by intervening manipulation. I have no idea what I'm talking about, here, but don't think that I've seen any reports of people having complete success operating a Photos Library from RAID storage.

Do you know other people doing this?

Since I don't use iCloud Library I can't advise any further. It would be just a guess. Hopefully, Richard.Taylor will be by and, since he's of the two reigning Photos gurus here, he should be able to advise more accurately.

pdibello wrote:…I am curious as to what you mean by "timing interference by intervening manipulation".

I tried to answer that with "I have no idea what I'm talking about, here, "

It is hard to imagine that Photos would work differently on RAID than not, since I know that most video professionals (and I suspect most photo professionals) use either RAID of HDDs or NAS. Gosh, I hope that Photos uses the File System, and does not need to "go beneath it," but who knows.

I think that Photos depends heavily on the processes used in Apple's own formats. We know it has problems with things not connected directly by cable, and we know that it doesn't work well with NAS.

So, it seems as though you suggest that I "shrug" and live with this, since it seems to have no ill effects?

I'm saying, if it were me, I'd continued playing with the RAID system, but that I would be making frequent backups on a separate APSF formatted hard drive, keeping them each at least a month, in case I later found that something had gone horribly wrong.

How many videos do you have in the library and how big are they. Why - because Photos will examine every frame of each video to categorize faces, objects, plants, animals, etc.

pdibello wrote: …Indeed, I am well back up.

Good-- we have seen instances when corruption occurs, but the symptoms don't appear until long afterward. Kind of like cancer, I guess.