From owner-svn-src-head@freebsd.org Mon Nov 20 21:57:24 2017 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 83925DF69FD; Mon, 20 Nov 2017 21:57:24 +0000 (UTC) (envelope-from brooks@spindle.one-eyed-alien.net) Received: from spindle.one-eyed-alien.net (spindle.one-eyed-alien.net [199.48.129.229]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 622F46F33A; Mon, 20 Nov 2017 21:57:24 +0000 (UTC) (envelope-from brooks@spindle.one-eyed-alien.net) Received: by spindle.one-eyed-alien.net (Postfix, from userid 3001) id D8D585A9F27; Mon, 20 Nov 2017 21:57:16 +0000 (UTC) Date: Mon, 20 Nov 2017 21:57:16 +0000 From: Brooks Davis To: Edward Tomasz Napierala Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r325965 - head/libexec/rtld-elf Message-ID: <20171120215716.GA2442@spindle.one-eyed-alien.net> References: <201711181321.vAIDLM6S028725@repo.freebsd.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="XsQoSWH+UP9D9v3l" Content-Disposition: inline In-Reply-To: <201711181321.vAIDLM6S028725@repo.freebsd.org> User-Agent: Mutt/1.9.1 (2017-09-22) X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 20 Nov 2017 21:57:24 -0000 --XsQoSWH+UP9D9v3l Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Nov 18, 2017 at 01:21:22PM +0000, Edward Tomasz Napierala wrote: > Author: trasz > Date: Sat Nov 18 13:21:22 2017 > New Revision: 325965 > URL: https://svnweb.freebsd.org/changeset/base/325965 >=20 > Log: > Increase rtld initial memory pool size from 32kB to 128kB. > =20 > The old value was probably fine back in 1998, when that code was import= ed > (although the comments still mention VAX, which was quite obsolete by t= hen); > now, however, it's too small to handle our libc, which results in some > additional calls to munmap/mmap later on. Asking for more virtual addr= ess > space is virtually free, and syscalls are not, thus the change. Not specificaly about this commit, but a general comment: The power-of-2 sized buckets used by this allocator are likely suboptimal both in terms of space use (largely irrelevent in practice) and cache effects (in particular, unnecessicary false sharing of TLS segments). There is probably a fair bit of room for optimization here. -- Brooks --XsQoSWH+UP9D9v3l Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEcBAEBAgAGBQJaE0+8AAoJEKzQXbSebgfAAhcH/24sopp2YZqH4t8QUOuQrOzE t+7y4BPiFNEACGiPJzdi+CYU3zKkNeZ1oINa8hQk4qJHKh84TgStxt2jbA4i7o15 Qb1VE9InSGiGg6Za96/dzbgH3oQm6leuFAICDQ2GRjucm+F3KwfxwxmQZvmee36S yjfrQTDTaLh99K+e0GBGqaHIzFnDH1XOs8Pzk1L5Mhx9Zr+6FV1jhFwvZTKP3P6M KMtGjz3quNuLky1QGyZzAxDEb45x9Uwm1IAx0iegFptJ5Ewts+hU0NMfymRN7oTe cIYiGfKsUlojchQawml1Uu6a6tlCyvj5VDRBYHQOgzIBbaDnrsntRRmkbDo1aTk= =SUiO -----END PGP SIGNATURE----- --XsQoSWH+UP9D9v3l--