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Date:   Thu, 23 Jul 2020 20:29:23 -0700
From:   Andi Kleen <ak@linux.intel.com>
To:     kan.liang@linux.intel.com
Cc:     peterz@infradead.org, acme@redhat.com, mingo@kernel.org,
        linux-kernel@vger.kernel.org, jolsa@kernel.org, eranian@google.com,
        alexander.shishkin@linux.intel.com, like.xu@linux.intel.com
Subject: Re: [PATCH V7 12/14] perf, tools, stat: Support new per thread
 TopDown metrics
Message-ID: <20200724032923.GB1180481@tassilo.jf.intel.com>
References: <20200723171117.9918-1-kan.liang@linux.intel.com>
 <20200723171117.9918-13-kan.liang@linux.intel.com>
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> +		if (topdown_metric_attrs[0] && str) {`
> +			if (!stat_config.interval) {
> +				fprintf(stat_config.output,
> +					"Topdown accuracy may decreases when measuring long period.\n"
> +					"Please print the result regularly, e.g. -I1000\n");

Can you disable this warning when --metrics-only is used? In this case it doesn't matter
because the error is proportional to the percentage accuracy and should be invisible.

You can only see a difference when looking at the expanded counts.

-andi