4890b686f4
Currently, tcp_memory_allocated can hit tcp_mem[] limits quite fast. Each TCP socket can forward allocate up to 2 MB of memory, even after flow became less active. 10,000 sockets can have reserved 20 GB of memory, and we have no shrinker in place to reclaim that. Instead of trying to reclaim the extra allocations in some places, just keep sk->sk_forward_alloc values as small as possible. This should not impact performance too much now we have per-cpu reserves: Changes to tcp_memory_allocated should not be too frequent. For sockets not using SO_RESERVE_MEM: - idle sockets (no packets in tx/rx queues) have zero forward alloc. - non idle sockets have a forward alloc smaller than one page. Note: - Removal of SK_RECLAIM_CHUNK and SK_RECLAIM_THRESHOLD is left to MPTCP maintainers as a follow up. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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.