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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: BCCC3C000C X-Rspamd-Server: rspam02 X-Stat-Signature: 174orbx9rtsx1xoujeutc7nnhisei39w X-HE-Tag: 1760429860-371302 X-HE-Meta: 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 9CSLv1A6 3pFQh/DDbtvWaTiyWoNi1RGwAD4sW1e5uldzgKYo+qTiZ8ojpalH7ZzJvQNuD7zj85+5XRy++ntNLOETO8OfJvG7TisefcNZq6cgCVb1gRroJpIotAiOO7lttWxj+/lbS/xtTcl1OCK2/AH1PrieanQBsZCHdgvFxBrUZwdUdwgZWOtocf1hDKa9ZyTKPus8oTcsR3EmAO1y+qsT1bJZot5uCUS3YJi6nyy8Ha+1/ucFeDFQ7fUYQfdwC03ZtxkuhnY5I/QfjEACUtEw6Rh1WVkqIEH3Iku6eP/ot3qfxhp3uDuQ3eU6iyPHSKjXVwmz+55XBjvBhJ4wgOVBWvMA1JEzul6Zbv34iYV3Nl36qtRP1ZPCVi+v4LmPoeT9YO3m74bVqOWLcTa52LYUONsaiU5UOXA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Oct 14, 2025 at 3:01=E2=80=AFPM Eric Dumazet = wrote: > > On Mon, Oct 13, 2025 at 11:43=E2=80=AFPM Barry Song <21cnbao@gmail.com> w= rote: > > > > > > > > > > A problem with the existing sysctl is that it only covers the TX pa= th; > > > > for the RX path, we also observe that kswapd consumes significant p= ower. > > > > I could add the patch below to make it support the RX path, but it = feels > > > > like a bit of a layer violation, since the RX path code resides in = mm > > > > and is intended to serve generic users rather than networking, even > > > > though the current callers are primarily network-related. > > > > > > You might have a buggy driver. > > > > We are observing the RX path as follows: > > > > do_softirq > > taskset_hi_action > > kalPacketAlloc > > __netdev_alloc_skb > > page_frag_alloc_align > > __page_frag_cache_refill > > > > This appears to be a fairly common stack. > > > > So it is a buggy driver? > > No idea, kalPacketAlloc is not in upstream trees. > > It apparently needs high order allocations. It will fail at some point. > > > > > > > > > High performance drivers use order-0 allocations only. > > > > > > > Do you have an example of high-performance drivers that use only order-= 0 memory? > > About all drivers using XDP, and/or using napi_get_frags() > > XDP has been using order-0 pages from the very beginning. Thanks! But there are still many drivers using netdev_alloc_skb()=E2=80=94w= e shouldn=E2=80=99t overlook them, right? net % git grep netdev_alloc_skb | wc -l 359 Thanks Barry