bridge cant handle large folders

you had one job...!

21000 jpegs in a folder.  Xn view can handle it with no problem.  Bridge absolutely chokes.  Its interface becomes unusably slow, moving from one image to the next takes seconds. 

It doesn't appear to be busy creating thumbnails, and I've left it for hours seeing if it will cache, but its just as useless at the end.  The folder is 180gb.

so how big a folder can it handle?