As seen in Not enough free space, pulling a commit that unlocks a lot of large files whose content is present in the repository can result in an unexpected doubling of the disk space used by git-annex.

annex.diskreserve avoids that using up the entire disk, but it's not uncommon for users to not have it set, and the 1 mb default can easily be eaten up by other non-object uses of disk.

Perhaps 1 mb is too small for the default for annex.diskreserve. Even 10 or 100 mb would leave a lot more margin for other minor uses of disk space. (Update: increased default to 100 mb)

Perhaps there could be another config like annex.diskreserve but that applies only to populating unlocked files. It could default to some larger size, like 1 gb. Probably most users are not going to want to populate unlocked files when their disk space gets that low. Although, the same could be argued about just getting files. --Joey