I've started work on parallel get. Today, laid the groundwork in two areas:
Evalulated the ascii-progress haskell library. It can display multiple progress bars in the terminal, portably, and its author Pedro Tacla Yamada has kindly offered to improve it to meet git-annex's needs.
I ended up filing 10 issues on it today, around 3 of the are blockers for git-annex using it.
Worked on making --quiet more quiet. Commands like rsync and wget need to have thier progress output disabled when run in parallel.
Didn't quite finish this yet.
Yesterday I made some improvements to how git-annex behaves when it's passed a massive number of directories or files on the command line. Eg, when driven by xargs. There turned out to be some bugs in that scenario.
One problem one I kind of had to paper over. While git-annex get normally is careful to get the files in the same order they were listed on the command line, it becomes very expensive to expand directories using git-ls-files, and reorder its output to preserve order, when a large number offiles are passed on the command line. There was a O(N*M) time blowup.
I worked around it by making it only preserve the order of the first 100 files. Assumption being that if you're specifying so many files on the command line, you probably have less of an attachment to their ordering.