[Xapian-discuss] Testing document size preallocation.

[Shane Spencer]

https://gist.github.com/ad2accc5b4655753923d

So here I am creating a database with no values for each small
document and one with a bunch of blank values (uuid_blank).  Once
those are flushed then I reopen them and start replacing the documents
of each with identical documents that have an identical large set of
values.  I am using replace_document and a specific document ID.

Is there a specific problem that I'm up against that shows that
preallocation is up to 2 times slower for replacing an identically
sized document rather than adding to its final serialized size?

- Shane