From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 98FF35B1EA for ; Tue, 9 Apr 2024 22:49:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712702969; cv=none; b=i3VVxNVnnLR+pDZohvvCRgkjzcx3pMg47BeVUq6+uro7EKAI95BSf/0Ybb3nnvkU72y4BRtnAaR0ZUmbesuVEV3h/VfDPiUxgGzr8+0mAB6gHpCJnGeSGWeKVaih2LEtakCWcnCTfjFQppmsNKnFrxWxtyz3P0vTTY9M/jSmM/Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712702969; c=relaxed/simple; bh=pHkGzG7uY0hK1agTCuiDlZZKkMXpmtSgWgjAy8SNNHY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=CUPbBTtlVng5JFWQw6u+QP+cOMJYCYa2v+n8NE7Jtr3aURCFPwvW62EpQwz82mCcPmLjPtS8sTvRRppD4YFIk8GksfCbwiRl3VUkVxpH+On28FsIhVcBdYUUCUQEBxX/2Ts9rBkjM82UZlXMbBc2SVmm9hOOHRYuk8xeax2NLZo= 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=YktLj9do; arc=none smtp.client-ip=209.85.215.202 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="YktLj9do" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-5dbddee3694so3260874a12.1 for ; Tue, 09 Apr 2024 15:49:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1712702967; x=1713307767; 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=X7BDOAdXGb6PM9j/Ro0cuDsmudWi0lw4fAoXWjZNUDM=; b=YktLj9dol0vzt94nWv27n4IvO9JYLCGzZau3EWPMxfmyMJNgADVzHHUW3XkJ7g0jBP +8LFnhjnwWgqMAI/FoLbYXDyo9zEN8HlrxEvmPmboc56kEPxmgYogKAsDEj2O2k8nf5y FiuQ64xEUW4dpafMfKg/zyrvY5M3jEBxpbMbQHxpPnpZKl87r1s77Zj7+5IQfXVuFj9E 7orNEsz/OX3iqV+pN/QB/GMYZK0yDJfgug4ClxMFgSrHWGbZKNXFgM358EKww5ev+t98 x3jNCc4LZk98tdhIGiIyr2m/J7ANDw85ZMKMUh466YpwdrERTgpH1Ut9w8WI10ieM0YN mvZw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1712702967; x=1713307767; 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=X7BDOAdXGb6PM9j/Ro0cuDsmudWi0lw4fAoXWjZNUDM=; b=UF8WDJNYmSXtWr8e4tUprEEQfM5tfp0NTFiIEDWjNPaLPgC+MHiQA1yThQvZemb64r /oz0p1C4TlMvOfIYuoIe4JkwEUuhpotiJIuST/ekEOrk7N6qEy4tn8s+Xea5CegGATRN iOc5HTD8czfKIpwsfZcuiG89CIxy5moUCtUZzJCHvJEUvPsh4pZ3Bmg04c1II9sT2daA cs8iiV9lbYuBjNgzIcQsOPzjSze5nf0ApDr+e5vkf33bw8xzfZRhsknqm0fsNDFx4vrG zVcFea/qbXxPXTf5BkYlKev1J4UlPt/DWscBBBNTOcktgFpsYJVKS04RL2HpLbqi3f6F GkRQ== X-Forwarded-Encrypted: i=1; AJvYcCW2BsyHkACtS5nmTIvcs17Ivv7ZiG7pKM7v9ld9Zd/l9b9JJr4yExxMyEgAkZWhMcnDEB8RhgU6TPldKEkDpcvzAitP X-Gm-Message-State: AOJu0YzTciB6QOHWseBYNnlyOUa4LYDXleP5sNDmnP/9EodkaKFeQJ/g vPz8E96IJnpn+MMRZZCNrjgN7Rspilq5dcMpJpT6PLilRQKOMvKh7Vjdb7psbHbumpSEWlcBqxE j4w== X-Google-Smtp-Source: AGHT+IGuB80kepjVY6GU7N10vM5dzh4IgkERFfdumXmvvWAycN/WJPPjMEVepXbJZUSB39DoOq+2y2AV3HE= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a65:6c16:0:b0:5dc:4a5f:a5ee with SMTP id y22-20020a656c16000000b005dc4a5fa5eemr27846pgu.1.1712702966899; Tue, 09 Apr 2024 15:49:26 -0700 (PDT) Date: Tue, 9 Apr 2024 15:49:25 -0700 In-Reply-To: <20240215235405.368539-11-amoorthy@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240215235405.368539-1-amoorthy@google.com> <20240215235405.368539-11-amoorthy@google.com> Message-ID: Subject: Re: [PATCH v7 10/14] KVM: selftests: Report per-vcpu demand paging rate from demand paging test From: Sean Christopherson To: Anish Moorthy Cc: oliver.upton@linux.dev, maz@kernel.org, kvm@vger.kernel.org, kvmarm@lists.linux.dev, robert.hoo.linux@gmail.com, jthoughton@google.com, dmatlack@google.com, axelrasmussen@google.com, peterx@redhat.com, nadav.amit@gmail.com, isaku.yamahata@gmail.com, kconsul@linux.vnet.ibm.com Content-Type: text/plain; charset="us-ascii" On Thu, Feb 15, 2024, Anish Moorthy wrote: > Using the overall demand paging rate to measure performance can be > slightly misleading when vCPU accesses are not overlapped. Adding more > vCPUs will (usually) increase the overall demand paging rate even > if performance remains constant or even degrades on a per-vcpu basis. As > such, it makes sense to report both the total and per-vcpu paging rates. > > Signed-off-by: Anish Moorthy > --- > tools/testing/selftests/kvm/demand_paging_test.c | 15 +++++++++++---- > 1 file changed, 11 insertions(+), 4 deletions(-) > > diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c > index 09c116a82a84..6dc823fa933a 100644 > --- a/tools/testing/selftests/kvm/demand_paging_test.c > +++ b/tools/testing/selftests/kvm/demand_paging_test.c > @@ -135,6 +135,7 @@ static void run_test(enum vm_guest_mode mode, void *arg) > struct timespec ts_diff; > struct kvm_vm *vm; > int i; > + double vcpu_paging_rate; > > vm = memstress_create_vm(mode, nr_vcpus, guest_percpu_mem_size, 1, > p->src_type, p->partition_vcpu_memory_access); > @@ -191,11 +192,17 @@ static void run_test(enum vm_guest_mode mode, void *arg) > uffd_stop_demand_paging(uffd_descs[i]); > } > > - pr_info("Total guest execution time: %ld.%.9lds\n", > + pr_info("Total guest execution time:\t%ld.%.9lds\n", > ts_diff.tv_sec, ts_diff.tv_nsec); > - pr_info("Overall demand paging rate: %f pgs/sec\n", > - memstress_args.vcpu_args[0].pages * nr_vcpus / > - ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / NSEC_PER_SEC)); > + > + vcpu_paging_rate = > + memstress_args.vcpu_args[0].pages > + / ((double)ts_diff.tv_sec > + + (double)ts_diff.tv_nsec / NSEC_PER_SEC); *sigh* For the umpteenth time, please follow kernel coding style. Either vcpu_paging_rate = memstress_args.vcpu_args[0].pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / NSEC_PER_SEC); or vcpu_paging_rate = memstress_args.vcpu_args[0].pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / NSEC_PER_SEC); I don't have a strong preference, so I'll go with the first one when applying.