Large uploads (e.g. ~800 MB ISOs) could OOMKill the process, even on
dedup hits, due to three separate full-file-in-memory paths:
- NextCloud PUT (/remote.php/dav) buffered the entire body in RAM via
body::to_bytes before any dedup logic, then re-wrote and re-hashed it.
Now streams the body to a temp file with incremental BLAKE3 and goes
through update_file_streaming (shared spool helper with the native
WebDAV PUT handler); peak heap is ~one HTTP frame regardless of size.
- DedupService::store_chunks materialized every new chunk's data in a Vec
before uploading. Now reads each new chunk by positioned I/O
(read_exact_at, off the runtime via spawn_blocking) just before its
upload; peak heap bounded to ~CHUNK_UPLOAD_CONCURRENCY x CDC_MAX_CHUNK.
- The upload spool used the OS temp dir, often tmpfs/RAM in containers
where its page-cache counts against the cgroup memory limit. Add
OXICLOUD_UPLOAD_TMPDIR to point the spool at real disk.
Also collapse a pre-existing clippy collapsible_else_if in carddav_handler.
Refs #404
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>