Reusing http connection when operating on chunks is not done yet,
I had to submit some patches to DAV to support that. However, this is no
slower than old-style chunking was.
Note that it's a fileRetriever and a fileStorer, despite DAV using
bytestrings that would allow streaming. As a result, upload/download of
encrypted files is made a bit more expensive, since it spools them to temp
files. This was needed to get the progress meters to work.
There are probably ways to avoid that.. But it turns out that the current
DAV interface buffers the whole file content in memory, and I have
sent in a patch to DAV to improve its interfaces. Using the new interfaces,
it's certainly going to need to be a fileStorer, in order to read the file
size from the file (getting the size of a bytestring would destroy
laziness). It should be possible to use the new interface to make it be a
byteRetriever, so I'll change that when I get to it.
This commit was sponsored by Andreas Olsson.
Suppose A is 10 mb, and B is 20 mb, and the upload speed is the same. If B
starts first, when A will overwrite the file it is uploading for the 1st chunk.
Then A uploads the second chunk, and once A is done, B finishes the 1st chunk
and uploads its second. We now have 1(from A), 2(from B), so data loss.
The benefit of using a compatable directory structure does not outweigh the
cost in complexity of handling the multiple locations content can be stored
in directory special remotes. And this also allows doing away with the parent
directories, which can't be made unwritable in DAV, so have no benefit
there. This will save 2 http calls per file store.
But, kept the directory hashing, just in case.
