The round-robin walk capped what it listed, not what it read: every queued
folder was read whole, sorted and held until drained, so one GET could pull
millions of entries (100 folders of 50,000 files killed a 400 MB heap). A read
now keeps only the entries the listing can use, and MAX_WALK_ENTRIES_READ stops
opening folders at 250,000 entries, leaving the rest queued and flagged.
A folder also spent its whole share on its own files, leaving nothing for the
subfolders it had just found, alone in its round or beside a sibling, so search
hits inside them were lost. Its files now count as one more share beside those
subfolders. Math.max(directoriesInRound, 2) would have fixed only the sole-folder
case and cut a wide root's folder list short.
Folders below the walk root are probed before their readdir (#516), since the
walk reaches folders the depth-first one never did.
Filtering at the read also clears the false flag on a folder whose only unread
entries were hidden or excluded, and an exactly-full workspace now finishes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>