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Date: Tue, 21 Sep 2010 19:42:02 +0200
Subject: Re: [PATCH 03/10] jump label v11: base patch
From: "Andi Kleen" <andi@firstfloor.org>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Steven Rostedt" <rostedt@goodmis.org>, "Andi Kleen" <andi@firstfloor.org>,
        "Jason Baron" <jbaron@redhat.com>, linux-kernel@vger.kernel.org,
        mingo@elte.hu, mathieu.desnoyers@polymtl.ca, tglx@linutronix.de,
        roland@redhat.com, rth@redhat.com, mhiramat@redhat.com,
        fweisbec@gmail.com, avi@redhat.com, davem@davemloft.net,
        vgoyal@redhat.com, sam@ravnborg.org, tony@bakeyournoodle.com
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>
> If all you need is exact matches -- as in this case -- hashes are
> generally faster than binary anyway.

Actually only if you have the whole thing in cache. The binary
search has a much nicer access pattern if it's cache cold.

And the footprint of directly accessing the section than having
separate large list and tables is also significantly more
compared to a compact table.

But I don't think the access speed really matters here. Toggling
trace points should be rare and is not a critical path
operation. What matters is runtime overhead and simplicity.

Right now on the simplicity front there is a problem.

-Andi