diff options
| author | Stefano Garzarella <sgarzare@redhat.com> | 2021-10-26 18:23:44 +0200 |
|---|---|---|
| committer | Kevin Wolf <kwolf@redhat.com> | 2021-11-02 13:03:30 +0100 |
| commit | 684960d46267d6e6443b39ee98b3a95632ba8dc6 (patch) | |
| tree | d265c1c5e59a570e2a7bab20225b2a2d8014e47c /qapi | |
| parent | 304332039014679b809f606e2f227ee0fc43a451 (diff) | |
| download | focaccia-qemu-684960d46267d6e6443b39ee98b3a95632ba8dc6.tar.gz focaccia-qemu-684960d46267d6e6443b39ee98b3a95632ba8dc6.zip | |
file-posix: add `aio-max-batch` option
Commit d7ddd0a161 ("linux-aio: limit the batch size using
`aio-max-batch` parameter") added a way to limit the batch size
of Linux AIO backend for the entire AIO context.
The same AIO context can be shared by multiple devices, so
latency-sensitive devices may want to limit the batch size even
more to avoid increasing latency.
For this reason we add the `aio-max-batch` option to the file
backend, which will be used by the next commits to limit the size of
batches including requests generated by this device.
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20211026162346.253081-2-sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qapi')
| -rw-r--r-- | qapi/block-core.json | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/qapi/block-core.json b/qapi/block-core.json index ce2c1352cb..ea36e0038c 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -2939,6 +2939,12 @@ # for this device (default: none, forward the commands via SG_IO; # since 2.11) # @aio: AIO backend (default: threads) (since: 2.8) +# @aio-max-batch: maximum number of requests to batch together into a single +# submission in the AIO backend. The smallest value between +# this and the aio-max-batch value of the IOThread object is +# chosen. +# 0 means that the AIO backend will handle it automatically. +# (default: 0, since 6.2) # @locking: whether to enable file locking. If set to 'auto', only enable # when Open File Descriptor (OFD) locking API is available # (default: auto, since 2.10) @@ -2968,6 +2974,7 @@ '*pr-manager': 'str', '*locking': 'OnOffAuto', '*aio': 'BlockdevAioOptions', + '*aio-max-batch': 'int', '*drop-cache': {'type': 'bool', 'if': 'CONFIG_LINUX'}, '*x-check-cache-dropped': { 'type': 'bool', |