This improves the borg special remote memory usage, by
letting it only load one archive's worth of filenames into memory at a
time, and building up a larger tree out of the chunks.
When a borg repository has many archives, git-annex could easily OOM
before. Now, it will use only memory proportional to the number of
annexed keys in an archive.
Minor implementation wart: Each new chunk re-opens the content
identifier database, and also a new vector clock is used for each chunk.
This is a minor innefficiency only; the use of continuations makes
it hard to avoid, although putting the database handle into a Reader
monad would be one way to fix it.
It may later be possible to extend the ImportableContentsChunkable
interface to remotes that are not third-party populated. However, that
would perhaps need an interface that does not use continuations.
The ImportableContentsChunkable interface currently does not allow
populating the top of the tree with anything other than subtrees. It
would be easy to extend it to allow putting files in that tree, but borg
doesn't need that so I left it out for now.
Sponsored-by: Noam Kremen on Patreon
When the progress display gets longer, and then shorter again, it causes
the cursor to jitter back and forth. Somehow I never noticed this until
this morning, but then it became intolerable to watch.
To fix it, pad the progress display to the maximum length it's occupied.
Sponsored-by: Svenne Krap on Patreon
All backends use genKeyName, which uses preSanitizeKeyName, which will
escape newlines.
I suspect this newline prevention was added back when git-annex was
reading the output of sha1sum..
Sponsored-by: Kevin Mueller on Patreon
This adds the overhead of a copy when serializing and deserializing keys.
I have not benchmarked much, but runtimes seem barely changed at all by that.
When a lot of keys are in memory, it improves memory use.
And, it prevents keys sometimes getting PINNED in memory and failing to GC,
which is a problem ByteString has sometimes. In particular, git-annex sync
from a borg special remote had that problem and this improved its memory
use by a large amount.
Sponsored-by: Shae Erisson on Patreon
This adds the overhead of a copy whenever converting to/from ExportLocation and
ImportLocation.
borg: Some improvements to memory use when importing a lot of archives.
(It's still pretty bad.)
Sponsored-by: Mark Reidenbach on Patreon
