mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-03-21 23:12:32 -04:00
4d9237e32c
Particularly for networked workloads, io_uring intensively uses its poll based backend to get a notification when data/space is available. Profiling workloads, we see 3-4% of alloc+free that is directly attributed to just the apoll allocation and free (and the rest being skb alloc+free). For the fast path, we have ctx->uring_lock held already for both issue and the inline completions, and we can utilize that to avoid any extra locking needed to have a basic recycling cache for the apoll entries on both the alloc and free side. Double poll still requires an allocation. But those are rare and not a fast path item. With the simple cache in place, we see a 3-4% reduction in overhead for the workload. Signed-off-by: Jens Axboe <axboe@kernel.dk>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.