@samitouri / QOSamiQemu / commits / 40ee2ff0ce

qapi/block-export: Document FUSE's multi-threading

Document for users that FUSE's multi-threading implementation distributes requests in a round-robin manner, regardless of where they originate from. As noted by Stefan, this will probably change with a FUSE-over-io_uring implementation (which is supposed to have CPU affinity), but documenting that is left for once that is done. Suggested-by: Stefan Hajnoczi <stefanha@redhat.com> Acked-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Hanna Czenczek <hreitz@redhat.com> Message-ID: <20260309150856.26800-25-hreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Hanna Czenczek committed Mar 9, 2026 at 16:08 UTC 40ee2ff0ce68f42916146b49943e4872dc90460d
1 file changed +5
qapi/block-export.json
+5
@@ -164,6 +164,11 @@
164 # Options for exporting a block graph node on some (file) mountpoint
165 # as a raw image.
166 #
167 +# Multi-threading note: The FUSE export supports multi-threading.
168 +# Currently, requests are distributed across these threads in a
169 +# round-robin fashion, i.e. independently of the CPU core from which a
170 +# request originates.
171 +#
172 # @mountpoint: Path on which to export the block device via FUSE.
173 # This must point to an existing regular file.
174 #