Re: [PATCH v2 net-next 0/4] bpf: bpf_htab: Add BPF_MAP_TYPE_PERCPU_HASH

[David Miller]

From: Martin KaFai Lau <kafai@xxxxxx>
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.