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Subject: Re: UMA_ZONE_CACHESPREAD and uma_zsecond_add
To: Andriy Gapon <avg@FreeBSD.org>, freebsd-arch@FreeBSD.org,
 Jeff Roberson <jroberson@jroberson.net>
References: <76a47d9a-da39-75f4-5794-24724d0befc7@FreeBSD.org>
From: Andrew Gallatin <gallatin@cs.duke.edu>
Message-ID: <035f48ea-8722-f697-cc71-cb8ee772e062@cs.duke.edu>
Date: Sun, 12 Mar 2017 14:55:19 -0400
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On 03/08/2017 10:56, Andriy Gapon wrote:
>
> First, the history of UMA_ZONE_CACHESPREAD and uma_zsecond_add():
> https://lists.freebsd.org/pipermail/freebsd-arch/2008-December/008800.html
>
> Now, more than 8 years after those features were introduced, we still don't have
> a single in-tree consumer for them.
> Does anyone use those features out of tree?
> Does anyone still have plans to make use of them?
> Will anyone get sad if those features get garbage collected?

This is something that I keep getting suggestions to try at Netflix
on our 100G boxes.  From the description, it really seems like
it might help us to have a few data types allocated like this.

Can you give me, say, one month to look into this before axing
it?

Thanks,

Drew