From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm1-x32b.google.com (mail-wm1-x32b.google.com [IPv6:2a00:1450:4864:20::32b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id A9C2C3B2A4 for ; Tue, 15 Nov 2022 09:44:28 -0500 (EST) Received: by mail-wm1-x32b.google.com with SMTP id a11-20020a05600c2d4b00b003cf6f5fd9f1so10435173wmg.2 for ; Tue, 15 Nov 2022 06:44:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; 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=vkozg3vJYa/tM+3ULoh1SfoOn+O78Kxa/KbG0mFcbGc=; b=JAUHmDkuMARAm2Knajt9gNOuF2bIGcxIx2szaH7fJ6si6pzgO80T4kySTc0DjYExmI G413HDJdEBE1JsCr+mc2yEkE9doDYJRcw7v6267aVtg3I9sR33tAjUEmA/nNJJC2oC1z G9yYwmBb+TxNcOHkT0k3bQoVyQXN48IDkV2mqllvBt1NFFWO93bTPZoMOB4J+wJC9Gcd 6bCF75EemG+iJVgr1GtsbwQ2opMXjunUKZO0RhWOiPaJoY1jYKFJlecCgDZj4VKTEtSP 4H26jxYbeikBS7D3m0RvRtFFJF6M4D9gI/+tArsyDNAWJ2tgvUNBM4wr+yEoE6OTIH7O xMNg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=vkozg3vJYa/tM+3ULoh1SfoOn+O78Kxa/KbG0mFcbGc=; b=vCJzyez1lVyc6Kxn1rYb/EANfTd5DiYiZHUbqNeQqwMtTMDZssd0Cth9D1QnFnONMN vtMXL7OexOainWg92Jha2imdCI2WGxasfdLtJ86EXlVW8GUFbKQo/ve2SPTT6b3JfQ7a vj5ZM8Xp/bAk2RQX+Ket9FU1s2/o6xITomyUymUrp+OaGsoScBJAKYj2AEDCJiAlmBVV aySrJL7MS3M7YoJZaSfm6I5N7H/hlmYlYFkTEoSl8KrlBDP7NBh1LNtgxq94VjfLmJq9 1konnHEqCsfuIiKXu0NBoyNLS5VLRZpQvpgyp3igpNBc04CSyXxMAWHKlEAZDDUEu432 N7Rw== X-Gm-Message-State: ANoB5pn26ZbJ/QH8QPzMyjz6vVyNE4naqth79Q2w5CyZWSdi5as/RSya AxvzaCBw3pvS2r6RTl8lUImRuyA31eGmlt2honk= X-Google-Smtp-Source: AA0mqf6FX1ZN86FBH+3+88+gdCFq9BNcN/LcUZQL4KFYtjmEGZpeYHg5dWS63GWMiuKlPzTrS6QrPYlWY1jsNjBSGw8= X-Received: by 2002:a05:600c:3d8c:b0:3cf:a6e8:b59b with SMTP id bi12-20020a05600c3d8c00b003cfa6e8b59bmr609603wmb.128.1668523467389; Tue, 15 Nov 2022 06:44:27 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Dave Taht Date: Tue, 15 Nov 2022 06:44:12 -0800 Message-ID: To: Herbert Wolverson Cc: libreqos Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: Re: [LibreQoS] cpumap-pping 1.0 final X-BeenThere: libreqos@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: Many ISPs need the kinds of quality shaping cake can do List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Nov 2022 14:44:28 -0000 yay! https://twitter.com/mtrantalainen/status/1592525968861990914 On Tue, Nov 15, 2022 at 6:08 AM Herbert Wolverson via LibreQoS wrote: > > Hey! > > Just wanted to announce that cpumap-pping is now tagged as the 1.0 releas= e. > > The one major change from RC1 is that the xdp_pping utility no longer doe= s any cleaning - it just reports statistics. That makes its execution a LOT= faster, and removes a stalling issue that was showing up under heavy (5 gb= it/s+) load. > > Under the hood, each "report flow" now carries a "recycle time" and a "fr= esh data" flag. They are also stored in an "LRU map" rather than a strict h= ash map - so if the buffer fills up, it automatically (in kernel space) evi= cts (replaces) the oldest member rather than pausing to report the event. T= his in turn allows for all memory allocation to be up-front (on load), so t= here are no memory allocations or reallocations within the running RTT trac= king system. > > Once a "report flow" has achieved its target number of samples, it stops = collecting data. 30 seconds (by default, it's configurable) later, the flow= is "recycled" - its buffer is empties, "fresh data" is set to false, and t= he recycle time bumped to "now + 30 seconds". If data arrives, "fresh data"= is set to true - and the reporting tool will show the new data. If no data= arrives, the flow ages slowly to the bottom of the list and is replaced wi= th no memory allocation/deallocation/reallocation. > > This has largely eliminated the occasional variance in execution time (it= never spiked above 6000 nanoseconds to begin with; but now it's consistent= ly under 0.0005 ms added ping time; you won't notice it). More importantly,= it completely eradicated the high-load behavior of the xdp_pping sitting a= nd spinning for long periods of times under high lock contention. > > -- Herbert > _______________________________________________ > LibreQoS mailing list > LibreQoS@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/libreqos --=20 This song goes out to all the folk that thought Stadia would work: https://www.linkedin.com/posts/dtaht_the-mushroom-song-activity-69813666656= 07352320-FXtz Dave T=C3=A4ht CEO, TekLibre, LLC