From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 DF5AF25C835 for ; Mon, 9 Jun 2025 14:34:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749479647; cv=none; b=Z67UAkyfRb1UOMsuGr7mHZGTju9zSmxxfpmpMj80YzgRdjh2q1SQ6bBrToZqK5jenZTlo6ELRiBK6+ur5q1UL7A6x137dOR9j4HAQmvh665Y0UuO9UPcAwSpSD/g6uRY239rTi/bBx/FDKJ/ayNlBq3w22q8L8yiLdj+uCykOz0= 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=Qbh/Dd89; arc=none smtp.client-ip=209.85.214.201 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="Qbh/Dd89" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-234aceaf591so29514555ad.1 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=lists.linux.dev; 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=Qbh/Dd89vsL0ipYQytEFMH2krrz7rd6SxaIOt3k/xuu/b6OehwehvvETCrDaQA/efz EYuoGSZq6+gfuFaE+Bk2iP+GNLp4AB1GFC/BqQfYnVt4GpCHOmG+b6IGgWNyirWO7BCA WqabVWVqqTyYdTl8mU0awyzchEk+dBY84lUMhs2ViwWjDEO7GA+pB51e/Gal1T2ia7Dc NJ7ytG+nfWZnF2dzvXoBoXB2+V5XQyWw9y2GLuaXWJ3fKz+PR0nhmEbYsEXE8tsLqOIS ik/6XZVgMttw68N7ErQn+OG2LTwEDdNFNkwgjkoRs6UO3Wq8gyeqXsDXZvmwlceVmlIe mdQw== 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=wyg7LQMOuU+Qlz/Uf0ZcdZKg2NJDFkh/tX53nILJWE8YARmLGU4uAzxsQu5CmASj9b 5HTA+S1wvKmJ0ag2CiGsTvRrtTTry4bb7VjY69wOi2v6wIps4mRSX0EpLNumlpNw232L LFKl6wEFp4lmyJbnAaxfow2B5DiXRdEb8B2U5xuzEFNXFUOkmvmLxzbosHkJnJ6+yXGE TZ5cniVKFZQnjMy/4SlQwYmwP5fcu7LdjXCBc8Pk4oHXvlRP0FLwxGwlyR0UIicdBtyS T7JVp7G2LW65fE44s5KHho2u2ZtUVh1MaMLSrstjWGNS1yx3eCDPvnLBEMxNqGPmKODk kCrw== X-Forwarded-Encrypted: i=1; AJvYcCWLoH4TWS6F/6wUFGXFBb4SzcYwkRLfWZTZWLFADSx0atSEtgktyLbSxe/RBoJsdFgQkHM7TA==@lists.linux.dev X-Gm-Message-State: AOJu0YzVtBAkZzE71Qvgd2xYQd5czqazqAXG0OW3//8ToOcDeuK5wOgX QRJPJB1TbSBhmACACpPauGXHAlt/ijTOvFWk1WQV6okA46Z646L4a03eER8ZRZXk51TXE+oppiF M3p3SzQ== 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: iommu@lists.linux.dev 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