Aperture not building thumbnails

Question

Having a problem right now with generating thumbnails in Aperture 3.5.1.  Originally had another issue with iMovie seeing very few movies in my Aperture library.  I was able to import all files from all cameras into iMovie, and can see them if I import a sampling of them into another library.  Apple support suggested I rebuild my library, which revealed a few more, but still less than 5% of the total.
Apple then suggested I create a new library and import my existing library.  I was watching the progress bar near the end when Aperture crashed at completion.  I repaired the library and it began building thumbnails.  The process has been slow, with Aperture running at 100% CPU (one core--single thread?) and very low I/O on the disk.
The status freezes on one image when Aperture processes roughly 1000 thumbnails.  It says "Generating Thumbnails for [image]" "35,323 Remaining".  At first I thought Aperture may still be processing in the background, seeing how Aperture's CPU utilization remained in the 100% range and disk usage continued.  But when I quit Aperture and restart, it shows barely more progress than what was indicated in the status before quitting Aperture.  The particular images listed are fine, and the thumbnails are generated when Aperture is launched.
At this point, Aperture will not quit cleanly, or with a Force Quit.  Occasionally I've been able to use this suggestion:
https://discussions.apple.com/docs/DOC-3881
In other cases, Aperture seems to quit, but the entry remains in the Activity Monitor, with all accumulated stats, but 0% CPU.  I'm unable to launch Aperture at this time and must restart.  If I try to kill the process, the OS says it can't find it.  Could this be a Mavericks eccentricity?
When restarting the OS and Aperture, thumbnail generation continues from where it left off, and processes another 1000 images or so.  I did try repairing the database, and thumbnail generation continued, but eventually failed.
Occasionally, the com.apple.MediaLibraryService stops resonding in the Event Viewer.  This had not always correlated with the frozen progress bar.  In fact, thumbnails have continued to process when I've seen that hang in Event Viewer.  But it always has meant I need to take Aperture down forcefully.  Oddly, I do not have sharing previews enabled (set to never for now).
There are a few early articles, but they don't seem to offer any suggestions I have not tried, except to persist and restart Aperture each time this happens.  Could take 2-3 weeks at this rate if I need to restart every time the progress bar stops.  I have also tried clearing user and system cache a few times.
Apple second level support has been slow to respond, and I'm over 9 days into this process.  Has anyone experienced anything similar, or can offer any suggestions?

Answer 1

Is it only your current Aperture library, that is causing this trouble?
Or do you see the same problem, when working with a new test library?
Although otherwise operationally sound, some video in my original library was not viewable in the Media Browser (including iMovie), even after a repair and rebuild.
I created a new, empty library and imported my original library.  I described that process.  Aside from the crash near the end, it appears to have all my assets.  The project and image counts are the same.
The issues described about building thumbnails is in this new library.  Upon importing my original library, the new library began generating all new thumbnails.
If the thumbnail generation is only hanging for your current Aperture library, you may have imported corrupted media - image files, videos that cannot be processed, sound files.
I know exactly what you're talking about, and this was my first assumption as well.  As an Aperture 3 early adopter, I saw this issue countless times from failed imports.  But I have examined over 8 files that it has apparently hung on.  The thumbnails are fine!  I look at the assets, directly, and they are in perfect condition.  I expected to find corrupted TIFF files or bad thumbnails.  Neither were true.  If I request to generate it again, it works just fine.
Have you tried to remove the images from your Apeture library, that are shown in the message? Inspect them in the Finder and check the media type - jpeg, raw, video and check, if other Applications can open it.
Yes.
I do not have previews generated for nearly 2/3 of the images in my library, although I haven't seen reports about how this could be a problem.
UPDATE
Since my first post, I found a suggestion to regenerate all new thumbnails.  Days of time lost, but I restarted.  Still had a crash after about 1000 thumbnails.  com.apple.qtserver or something was hung.  Seemed only to launch occasionally after I restarted.  Thought this might be responsible for generating thumbnails for video.  So I did a search for all video files and let Aperture build these as I browsed through, page by page. 
Since that time, Aperture has been building thumbnails for 10 hours, the longest run yet.  Thumbnails are still generating VERY slowly, but I haven't seen a crash since.
Could it be the back and forth between images and video as it's generating thumbnails?