From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v2 net-next 0/4] bpf: bpf_htab: Add
 BPF_MAP_TYPE_PERCPU_HASH
Date: Tue, 12 Jan 2016 16:45:36 -0500 (EST)
Message-ID: <20160112.164536.17755595447757162.davem@davemloft.net>
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From: Martin KaFai Lau <kafai@fb.com>
Date: Tue, 12 Jan 2016 00:20:48 -0800

> BPF + kprobe is very useful in statistics collection.  In particular,
> bpf is strong in doing aggregation within the kernel instead of
> outputting a lot of raw samples to the userspace.
> 
> In some cases, bumping a counter/value of a particular key will have
> noticeable impact.  For example, doing statistics collection
> on received packets and aggregating them by network
> prefix (like /64 in IPv6).  Having a percpu value can help.

Please:

	http://marc.info/?l=linux-netdev&m=145248145925834&w=2

Thanks.