From owner-freebsd-hackers@FreeBSD.ORG  Mon Sep 20 18:32:02 2010
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 460A61065672;
	Mon, 20 Sep 2010 18:32:02 +0000 (UTC) (envelope-from avg@freebsd.org)
Received: from citadel.icyb.net.ua (citadel.icyb.net.ua [212.40.38.140])
	by mx1.freebsd.org (Postfix) with ESMTP id EBC1B8FC1B;
	Mon, 20 Sep 2010 18:31:58 +0000 (UTC)
Received: from odyssey.starpoint.kiev.ua (alpha-e.starpoint.kiev.ua
	[212.40.38.101])
	by citadel.icyb.net.ua (8.8.8p3/ICyb-2.3exp) with ESMTP id VAA17080;
	Mon, 20 Sep 2010 21:31:56 +0300 (EEST)
	(envelope-from avg@freebsd.org)
Message-ID: <4C97A89B.9070806@freebsd.org>
Date: Mon, 20 Sep 2010 21:31:55 +0300
From: Andriy Gapon <avg@freebsd.org>
User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US;
	rv:1.9.2.9) Gecko/20100909 Lightning/1.0b2 Thunderbird/3.1.3
MIME-Version: 1.0
To: Jeff Roberson <jroberson@jroberson.net>
References: <4C93236B.4050906@freebsd.org> <4C935F56.4030903@freebsd.org>
	<alpine.BSF.2.00.1009181221560.86826@fledge.watson.org>
	<alpine.BSF.2.00.1009181135430.23448@desktop>
	<4C95C804.1010701@freebsd.org>
	<alpine.BSF.2.00.1009182225050.23448@desktop>
In-Reply-To: <alpine.BSF.2.00.1009182225050.23448@desktop>
X-Enigmail-Version: 1.1.2
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Cc: Andre Oppermann <andre@freebsd.org>, Jeff Roberson <jeff@freebsd.org>,
	Robert Watson <rwatson@freebsd.org>, freebsd-hackers@freebsd.org
Subject: Re: zfs + uma
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 20 Sep 2010 18:32:02 -0000

on 19/09/2010 11:27 Jeff Roberson said the following:
> On Sun, 19 Sep 2010, Andriy Gapon wrote:
> 
>> on 19/09/2010 01:16 Jeff Roberson said the following:
>>> Additionally we could make a last ditch flush mechanism that runs on each cpu in
>>> turn and flushes some or all of the buckets in per-cpu caches. Presently that is
>>> not done due to synchronization issues.  It can't be done from a central place.
>>> It could be done with a callout mechanism or a for loop that binds to each core
>>> in succession.
>>
>> I like all of the tree above approaches.
>> The last one is a bit hard to implement, the first two seem easier.
> 
> All the last one requires is a loop calling sched_bind() on each available cpu.

Something like cache_drain() but with sched_bind() in the loop?
critical_enter() would be probably also needed to avoid preemption and conflict
while acting on cache buckets?

-- 
Andriy Gapon