From owner-dev-commits-src-main@freebsd.org Tue Feb 23 16:40:31 2021 Return-Path: Delivered-To: dev-commits-src-main@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 46F76549BFE; Tue, 23 Feb 2021 16:40:31 +0000 (UTC) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (br1.CN84in.dnsmgr.net [69.59.192.140]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4DlPtR01PDz3nBf; Tue, 23 Feb 2021 16:40:30 +0000 (UTC) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: from gndrsh.dnsmgr.net (localhost [127.0.0.1]) by gndrsh.dnsmgr.net (8.13.3/8.13.3) with ESMTP id 11NGeMsV017774; Tue, 23 Feb 2021 08:40:22 -0800 (PST) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.13.3/8.13.3/Submit) id 11NGeMsl017773; Tue, 23 Feb 2021 08:40:22 -0800 (PST) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <202102231640.11NGeMsl017773@gndrsh.dnsmgr.net> Subject: Re: git: 7d4c444374d5 - main - Bump CTL block backend threads from 14 to 32 per LUN. In-Reply-To: <202102231603.11NG3auF089038@gitrepo.freebsd.org> To: Alexander Motin Date: Tue, 23 Feb 2021 08:40:22 -0800 (PST) CC: src-committers@freebsd.org, dev-commits-src-all@freebsd.org, dev-commits-src-main@freebsd.org Reply-To: rgrimes@freebsd.org X-Mailer: ELM [version 2.4ME+ PL121h (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII X-Rspamd-Queue-Id: 4DlPtR01PDz3nBf X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[] X-BeenThere: dev-commits-src-main@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Commit messages for the main branch of the src repository List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Feb 2021 16:40:31 -0000 > The branch main has been updated by mav: > > URL: https://cgit.FreeBSD.org/src/commit/?id=7d4c444374d53e54ce197138df64bf40c1fb05a3 > > commit 7d4c444374d53e54ce197138df64bf40c1fb05a3 > Author: Alexander Motin > AuthorDate: 2021-02-23 15:58:56 +0000 > Commit: Alexander Motin > CommitDate: 2021-02-23 16:03:32 +0000 > > Bump CTL block backend threads from 14 to 32 per LUN. > > This makes random read benchmarks look better on a wide ZFS pools. > I am not sure where the original value goes from, but it is there > for too long now. I would think this should be bounded by the number of cores/threads in the system. What happens on a 4 thread system with this value? > > MFC after: 1 week > --- > sys/cam/ctl/ctl_backend_block.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/sys/cam/ctl/ctl_backend_block.c b/sys/cam/ctl/ctl_backend_block.c > index 7ec8e32f7338..f50e47a2a6c1 100644 > --- a/sys/cam/ctl/ctl_backend_block.c > +++ b/sys/cam/ctl/ctl_backend_block.c > @@ -226,7 +226,7 @@ struct ctl_be_block_io { > > extern struct ctl_softc *control_softc; > > -static int cbb_num_threads = 14; > +static int cbb_num_threads = 32; > SYSCTL_NODE(_kern_cam_ctl, OID_AUTO, block, CTLFLAG_RD | CTLFLAG_MPSAFE, 0, > "CAM Target Layer Block Backend"); > SYSCTL_INT(_kern_cam_ctl_block, OID_AUTO, num_threads, CTLFLAG_RWTUN, > -- Rod Grimes rgrimes@freebsd.org