From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <andi@firstfloor.org>
Subject: Re: Understanding perf mem -t load results
Date: Tue, 24 Dec 2013 03:18:22 +0100
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To: Manuel Selva <selva.manuel@gmail.com>
Cc: Andi Kleen <andi@firstfloor.org>, linux-perf-users@vger.kernel.org

> In my experiments I get LFB samples with weight equal or greater than
> local RAM samples, I should I interpret these values ?

The measured latency can include the pipeline latency.

> Moreover, because I am more interested in identifying remote memory
> accesses sources than in effective load latency weight, I am wondering
> if using the perf mem tool (using the
> MEM_INST_RETIRED.LATENCY_ABOVE_THRESHOLD event) is the best solution.
> Couldn't I use sampling on other events such as UNCORE ones more
> easily and efficiently ?

You cannot use uncore events to sample on IPs. 

-Andi