iTunes Library 2,700 Albums, 800 gbs - Thoughts?

One of iTunes' big pluses is that it does cope well with large libraries. If there is a limiting factor it is probably main memory - I have two libraries that most people would consider large: one has around 1800 live shows, all in ALAC format (1.1TB disc space), the other around 5600 albums in a mix of 256Kbps AAC and 256-320Kbps mp3 (950GB disc space). Both are stored on USB 3.0 external drives. No issues with performance, even when used with relatively low-end hardware - I have a Dell micro-desktop as my master system (Celeron J1800, 2.41GHz), Windows 10 Home 64-bit with 8GB memory. I do notice slight degradation in performance (just in things like scrolling, not in playback) on the laptop I use occasionally when on the road, which has a similar processor but only 2GB memory.

I've occasionally seen the reverse, where the number of albums reported in the UI is one or two more than expected, as result of the odd behavior that's been present in the last few releases of iTunes where songs don't always group correctly into albums, Normally (based on reports here) this seems to apply to new additions, but I have seen it a few times where an album that's been in my library for years suddenly - and for no discernable reason - splits into two.

These things can be difficult to spot! I tend to only see variances because I maintain an Access database to track my music collection and use some VBScripts to keep it in sync with the iTunes libraries.

The latter - the database actually pre-dates iTunes (and my usage of it) by many years, having started life as a FileMaker Pro database more than 20 years ago. The link with iTunes is a convenient way to add artist / album / track info for new updates, though it also includes details of stuff I have that's not in iTunes. It is also normalized in structure so I can track acquistions and plays for albums/shows, rather than per-song as iTunes does.

1. Main library (commercial releases) and live shows library on 2TB USB 3.0 drives, plus a spoken word library on a 1TB USB 3.0 drive.
2. Main library is a mix of CD imports (all 256K AAC) and digital download purchases (mainly from Amazon). The only conversions I do are for the live shows library, where I use Foobar 2000 to convert from FLAC (SHN for some older material) to ALAC.
3. Where tagging is required I use Foobar 2000.
4. Each library is backed up using Microsoft SyncToy (as described in turingtest2's user tip on Backup your iTunes for Windows library with SyncToy) to a portable USB drive. I use the backup of the main library to update a duplicate library (another 2TB USB drive) that's attached to my work PC. Since the backups are themselves complete, functional iTunes libraries (following the same principles described in Make a split library portable) I can connect one of these drives to any PC, SHIFT-start iTunes and select the iTunes Library.itl file on the external drive, and have the complete library available to me.

The most likely cause is albums being split, since recent releases of iTunes have had a tendency to do this (occasionally) even when you haven't altered or adjusted any metadata. I've not seen any evidence that iTunes gets the count of albums wrong (though this is easy to check in Albums view based on the grid layout - e.g., if your iTunes screens shows 8 albums per row then the number shown in the last row should be (total albums MOD 8).

I'm sure its been reported multiple times (I've done so a couple of times, once for incorrect grouping of newly added albums, once for it happening with existing library content). I'm not aware of any public-facing ticket system that Apple maintains (though it may be there if you register as a developer). As far as I can tell the issue is related to evaluation of iTunes' grouping rules - essentially the data is right but its interpretation in the presentation layer is inconsistent. Since its been an issue for several releases (it may go back as far as iTunes 12) I assume that there isn't a "simple fix" for it 😟.