But let's face it, the FileStorage ZODB was never intended as a high performance storage medium. It is an excellent python object store. If you are going to be uploading really large files, you will be much better off storing them in the local filesystem as independant objects (assuming that the files themselves are static), and putting references to them in the ZODB. There are a number of Products available from the zope.org site that allow you to do just that.
Check out http://www.zope.org/Members/MacGregor/ExtFile and http://www.zope.org/Members/jfarr/Products/LocalFS
which were the first two that I found.
--sam
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