From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: passt.top; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: passt.top; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20230601 header.b=sKavi16w; dkim-atps=neutral Received: from mail-ed1-x532.google.com (mail-ed1-x532.google.com [IPv6:2a00:1450:4864:20::532]) by passt.top (Postfix) with ESMTPS id B5E685A061C for ; Tue, 28 Jan 2025 17:01:44 +0100 (CET) Received: by mail-ed1-x532.google.com with SMTP id 4fb4d7f45d1cf-5dc0522475eso11386975a12.1 for ; Tue, 28 Jan 2025 08:01:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1738080104; x=1738684904; darn=passt.top; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=D0k3fBlEMZejYNUo/PPRw/ypPzHY0k4b5+Q0BCJEkhc=; b=sKavi16wszfVIddhpHeB6147tYSy5gVk1mjkaTmsKWD6CzZZX46hB+e/E2fAJp9emb xUG3qi+zzB4jIqnemt67EP0sjsjpK3LCbjCqfnRAxtyzf/wu6Qiysq1HK9mhnQPojoVS DS9JvDipZ/D0NKWvUL0+N0gY2yPjCAlrhJqUltIGUqIasC3yhMbl1UkZfizG0rQzrOBC 6OgYwu1Ssl52Nwflv19rHfAD01YFAufYilowdsJb7XfER8xelKc68mWvfnjnR5qVdp2H 3rADy4RjW8+bFwotlKBGLydyCYhj5KJHSqgzpcJ+6twGcVEZMPpgVFFd9G2AeveJDlfx uGsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1738080104; x=1738684904; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=D0k3fBlEMZejYNUo/PPRw/ypPzHY0k4b5+Q0BCJEkhc=; b=EPkNo0ma4aaIW/zNSN8hbMxk8njOHTVEKjtRBKsZ49QWaAtF2MyGM1nJvInRgqajx/ Wz/yCorfzuG722ejZ4i8oJ8VU40G6ztnYOb+fnQkx5VEtkVhbtmQ5dp2OJKAB9dbicTj DgPNUSM10XeHcL9UJ4PGXWgrjQKH0tyF78Y3hkxwwBsP2gok2QGybQsze5CcuNHIv4vZ n1+zW7vqnGYi/7XEfnd1p/LhI4D61/YN4QrgBzHaECUIo2xNrn6Gl9C4GufSzGuZiBr4 kF0KAQmXZLu6VeigFABDu9kEeCIFTpGwSPfym2zxRTuqqUaYm5tlqnEuLYPzNn57deRN jwzg== X-Forwarded-Encrypted: i=1; AJvYcCWjcWC1fBtfccJcXc3bdKlmccJyyuyzUi32mkdw3kyfhZRIpVHJ0pRxNWWrap3s21txc+aypZInQKI=@passt.top X-Gm-Message-State: AOJu0YyDMFlYUI2+siFjjKoEzbvqYzwOoue7zgpWeHuD9njAaCehbJeW UfF18h9ZDQWZKvFcuXMbFyZgqpfn02RZmLCOEPXtCPVfTSD84g2JnsRojQ4qeegbjlGKR2eYuIs uqNBJn9oc7e4+l1ZegRoE8mtl32WuVE0v+A5k X-Gm-Gg: ASbGncvMOzf+zHYeTlsnOQHC8bCkv8ifkc1M088Vx42f6LHB+icLJmrN9bQcdN7khn5 0Bx08dshyoZncd1EoKcGCnRkaCC7yK2+KRutR6/lZPH3/cIVWPImM5xx7jRVUfmw/dqJ9VfLO X-Google-Smtp-Source: AGHT+IFKI9slu2MU1h5NPeLyxkc7rX7pm6YCOAXMlWPER9QnOkgaz0yoN+LppPpdVLAP4kKt9WlHfaHJiPi32hi8Se8= X-Received: by 2002:a05:6402:50cb:b0:5da:d16:7388 with SMTP id 4fb4d7f45d1cf-5db7d30063emr46797233a12.17.1738080102468; Tue, 28 Jan 2025 08:01:42 -0800 (PST) MIME-Version: 1.0 References: <20250127231304.1465565-1-jmaloy@redhat.com> In-Reply-To: From: Eric Dumazet Date: Tue, 28 Jan 2025 17:01:30 +0100 X-Gm-Features: AWEUYZnfRndrMm8DRxFHfmxsqyAbX4so8UYPqtYML_WF08_XVDHZvkww10r0usA Message-ID: Subject: Re: [net,v3] tcp: correct handling of extreme memory squeeze To: Neal Cardwell Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-MailFrom: edumazet@google.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation Message-ID-Hash: APIA2XVK42BLUWVNW77OAWAOUXUMZLG2 X-Message-ID-Hash: APIA2XVK42BLUWVNW77OAWAOUXUMZLG2 X-Mailman-Approved-At: Tue, 28 Jan 2025 17:05:29 +0100 CC: jmaloy@redhat.com, netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org, passt-dev@passt.top, sbrivio@redhat.com, lvivier@redhat.com, dgibson@redhat.com, memnglong8.dong@gmail.com, kerneljasonxing@gmail.com, eric.dumazet@gmail.com X-Mailman-Version: 3.3.8 Precedence: list List-Id: Development discussion and patches for passt Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Tue, Jan 28, 2025 at 4:57=E2=80=AFPM Neal Cardwell wrote: > > Yes, thanks for the fix. LGTM as well. > > Reviewed-by: Neal Cardwell > > BTW, IMHO it would be nice to have some sort of NET_INC_STATS() of an > SNMP stat for this case, since we have SNMP stat increases for other > 0-window cases. That could help debugging performance problems from > memory pressure and zero windows. But that can be in a separate patch > for net-next once this fix is in net-next. This is LINUX_MIB_TCPRCVQDROP ( TCPRcvQDrop )