From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AC49725D20A for ; Mon, 9 Jun 2025 14:34:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749479647; cv=none; b=omitYNsVAZQj/VL5C8YnWxFxBprLSZNUu8c256ezYqVWXyfyROAD93qwaV0oDhd1FaMG3T0Nhv6vGRbyhlBA1AXbvYZTD17sWrltmSMuFDzhRF1ezTkNDJUpqL3/QbRR7nQ0FPkb+jfe5PjPWaTnLY9GUW8ajo1J5AfljhGNxwA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749479647; c=relaxed/simple; bh=RncucRipf1cYTuMs00M4ActoK6bvKzfNJNtvT9JpgjU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=DkyMZTiIyzox37V7GkaXBz8rRK7CwPWW0ntxHkocDXFlvz2iNUTAM5dz1FlUTHy0KzvyFc0u8cIoeKqg0v92kO9S+VwTICCecYwBXnqch7rkEdw/527jVtJJ5SBzaAiv99TvFsbhjcrr8owPIEpiO/icZb9Jqx70ERCQb1oWR/I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=tNGVlTLA; arc=none smtp.client-ip=209.85.214.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tNGVlTLA" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-23507382e64so42485255ad.2 for ; Mon, 09 Jun 2025 07:34:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1749479645; x=1750084445; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=skrVgnKxd0KDctgtNsrczTFq3oqZuzABurM/ZDk3Ink=; b=tNGVlTLAOWVhh49MatYphHt8c38PXeIXC/VlqluEaGDCaoyMJqVzC66HbKX7dnIciH 0PGoW11+LTlJaPuNgr72xM74cHpJJlgoUrAhEKIDBHCNDumx7T3cqAAkYiYSz9umdvd6 kmZNaJ5To8WX0ozlVBlRWrfhJ3a92+7UAlxZr/NJzam14jVHklQ532oHIGlYi0Ok/Mzs Nq4VrgdsXK1fLnnkmsPK8l1DyGNrromCWfsrO934lBnczO0qHs3RFnoFkz8pNDt4nbMC ZONo2klPV1pEDG0x5E7WXJXaakcJM99AclD53gZJ24apACkzx17/9LVDmGt7crsgw3Du yLBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1749479645; x=1750084445; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=skrVgnKxd0KDctgtNsrczTFq3oqZuzABurM/ZDk3Ink=; b=fMAB/XFbzvFAsqU0g6GH7pWFZkmQ2zD1FcE93Q+rf7tpwlRI9KRfMJEQycqCORBP+o FjHPtDsnCCneWYu/PCNs2k03jCc6JHQjHdKnrFJPe2G8BCTo8VFBz/dMPsKPelkXhZwr 3fhfresSpN6rjguV1RjIIXhfCSS96aZpjm+SdQzxPVwQPemaObCkXVAY+MbgjbwWASHQ caTqeus5J+pZw14jHq8SA19evpoB21gZX85tocFL+gMpfwxQYrDrj1+3FHZ8FN2n9T3W O0fmqROBz7ZfAfBbLIGk+YRHMleY6+N7IimNC1hc4viuvzq16WNl4S/gSi/QSZGmxZHf rOBw== X-Forwarded-Encrypted: i=1; AJvYcCXYB+vE8M4dN3N3bkUod3rIDW++jRtFcpkL8g5lxWAvCy4f3J9J6SF32ffIca2QY34QwKPiNB4rCgqJfe0=@vger.kernel.org X-Gm-Message-State: AOJu0YwbZGxDccEJ6cU6VCp7NDtcAnmhPSacmopfSL/MTIcWmAl2Yzhp ZZJnCXkQsAyWLW1YDSe14LTMEa7sRJYbSpK/WLzEJLAwS2d3wdWVD4xUbCdDkAESfTZ3ALPVK86 2tgYYzg== X-Google-Smtp-Source: AGHT+IG0JGW+2ERvh9VAKD2SYT7EuVC5l/3/Q6a8vdYy73LZU6rmVVJeO2/2xeSR1j2Z/GlfjJU6yRXE7Fs= X-Received: from pjbsg3.prod.google.com ([2002:a17:90b:5203:b0:30e:6bb2:6855]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:c950:b0:234:b430:cea7 with SMTP id d9443c01a7336-23601cff140mr191326735ad.22.1749479645053; Mon, 09 Jun 2025 07:34:05 -0700 (PDT) Date: Mon, 9 Jun 2025 07:34:03 -0700 In-Reply-To: <20250609122050.28499-1-sarunkod@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250523010004.3240643-1-seanjc@google.com> <20250609122050.28499-1-sarunkod@amd.com> Message-ID: Subject: Re: [PATCH v2 00/59] KVM: iommu: Overhaul device posted IRQs support From: Sean Christopherson To: Sairaj Kodilkar Cc: baolu.lu@linux.intel.com, dmatlack@google.com, dwmw2@infradead.org, francescolavra.fl@gmail.com, iommu@lists.linux.dev, joao.m.martins@oracle.com, joro@8bytes.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, mlevitsk@redhat.com, pbonzini@redhat.com, vasant.hegde@amd.com Content-Type: text/plain; charset="us-ascii" On Mon, Jun 09, 2025, Sairaj Kodilkar wrote: > Hi Sean, > > Sorry for the delay in testing. All sanity tests are OK. I reran the performance > test on the V2 and noticed that V2 has significantly more GALOG entries than V1 > for all three cases. I also noticed that the Guest Nvme interrupt rate has > dropped for the 192 VCPUS. Hmm, I don't see any obvious bugs or differences (based on a code diffed between v1 and v2). I'll poke at the GALogIntr behavior just to double check, but my guess is that the differences are due to exernal factors, e.g. guest behavior, timing, scheduling, etc. IOPS are all nearly identical, so I'm not terribly concerned. > I haven't figured out what is causing this. Might just be slight differences in guest behavior? E.g. did you change the guest kernel? > I will continue my investigation further. > > VCPUS = 32, Jobs per NVME = 8 > ============================================================================================== > V2 V1 Percent change > ---------------------------------------------------------------------------------------------- > Guest Nvme interrupts 124,260,796 124,559,110 -0.20% > IOPS (in kilo) 4,790 4,796 -0.01% Uber nit, the percent change should be -0.10% > GALOG entries 8117 169 4702% > ---------------------------------------------------------------------------------------------- > > > VCPUS = 64, Jobs per NVME = 16 > ============================================================================================== > V2 V1 Percent change > ---------------------------------------------------------------------------------------------- > Guest Nvme interrupts 102,394,358 99,800,056 2.00% > IOPS (in kilo) 4,796 4,798 -0.04% > GALOG entries 19,057 11,923 59.83% > ---------------------------------------------------------------------------------------------- > > > VCPUS = 192, Jobs per NVME = 48 > ============================================================================================== > V2 V1 Percent change > ---------------------------------------------------------------------------------------------- > Guest Nvme interrupts 68,363,232 78,066,512 -12.42% > IOPS (in kilo) 4,751 4,749 -0.04% Uber nit #2, percent change should be postive 0.04%? 4,751 > 4,749. > GALOG entries 62,768 56,215 11.66% > ---------------------------------------------------------------------------------------------- > > Thanks > Sairaj