From owner-freebsd-fs@FreeBSD.ORG Fri Aug 23 22:54:59 2013 Return-Path: Delivered-To: fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 6A4E5ABD for ; Fri, 23 Aug 2013 22:54:59 +0000 (UTC) (envelope-from alfred@ixsystems.com) Received: from mail.iXsystems.com (newknight.ixsystems.com [206.40.55.70]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 4C60D2A25 for ; Fri, 23 Aug 2013 22:54:58 +0000 (UTC) Received: from localhost (mail.ixsystems.com [10.2.55.1]) by mail.iXsystems.com (Postfix) with ESMTP id 91ABF65101; Fri, 23 Aug 2013 15:54:58 -0700 (PDT) Received: from mail.iXsystems.com ([10.2.55.1]) by localhost (mail.ixsystems.com [10.2.55.1]) (maiad, port 10024) with ESMTP id 56963-07; Fri, 23 Aug 2013 15:54:58 -0700 (PDT) Received: from Alfreds-MacBook-Pro-9.local (unknown [10.8.0.10]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail.iXsystems.com (Postfix) with ESMTPSA id EB7BA650FC; Fri, 23 Aug 2013 15:54:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=ixsystems.com; s=newknight0; t=1377298498; bh=9MBg3K5GTmDODFSGs8YIgGglvpeG/+JWcp/Mpix/7hM=; h=Date:From:To:CC:Subject:References:In-Reply-To; b=pkjWadgyzuqSMxlLJhLx9qp29djY6ViTUthlt3YhMdbtEBpwIsyNYwxZcnpny/IvJ GDChDZ0PolmdKqw5/7LG2EurpVkT53vfAg7GbdA1AVd++96kqe52dlabZJvFQXAXLx w/tqrH0VmC4/2v2B5uHfVzH4yYbY/E7A/KxVg9Ow= Message-ID: <5217E841.9060504@ixsystems.com> Date: Fri, 23 Aug 2013 15:54:57 -0700 From: Alfred Perlstein User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: d@delphij.net Subject: Re: expand vfsops for compat References: <5217DF01.4070504@ixsystems.com> <5217E3AB.8070902@delphij.net> In-Reply-To: <5217E3AB.8070902@delphij.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: fs@freebsd.org X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Aug 2013 22:54:59 -0000 On 8/23/13 3:35 PM, Xin Li wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA512 > > On 08/23/13 15:15, Alfred Perlstein wrote: >> Index: sys/mount.h >> =================================================================== >> >> > - --- sys/mount.h (revision 254717) >> +++ sys/mount.h (working copy) @@ -628,6 +628,12 @@ >> vfs_susp_clean_t *vfs_susp_clean; vfs_notify_lowervp_t >> *vfs_reclaim_lowervp; vfs_notify_lowervp_t *vfs_unlink_lowervp; + >> vfs_mount_t *vfs_spare1; + vfs_mount_t *vfs_spare2; + vfs_mount_t >> *vfs_spare3; + vfs_mount_t *vfs_spare4; + vfs_mount_t >> *vfs_spare5; + vfs_mount_t *vfs_spare6; }; > Can this be just vfs_mount_t *vfs_spare[6]? Also, why 6 slots? (We > currently have 17 vfsops, 17+6=23 is a prime number but I don't think > we really need a prime number here :). > > Cheers, > - -- > Xin LI https://www.delphij.net/ > FreeBSD - The Power to Serve! Live free or die > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v2.0.21 (FreeBSD) > > iQEcBAEBCgAGBQJSF+OrAAoJEG80Jeu8UPuzJ50H/RRKhE87CQIqtagjc9ZtPx0P > 20x0gH3Smo3P8iWHr0Z4xGV3Vm+Hz2iua1aJzwQI7WeilHUd+xd7l/nnnLP83Mxh > l97mbfmXvBPHeJteuYtN5IbL7Z4qSY1IfJGAsIwUqMfSXk5UnSTK8aAM0vLhNPVb > TfEcR+xshqL3NDaqAPDp62I4F9Yma1heAHMlXO+jXm7Hy4VR9qVqGSLojdUUV6SV > PEVB0ulm34y0wGs4vRC9X6zQ1ndkKfZhvuJLmBP3U/bHvhE1yhTVNukWCysoOZ6Y > /RploLdpiOfKMcCy7vLdfiL1gy6Y7CVbOKpJRYleqrRa2AKBBenEfmmovQXgMrM= > =w0Ub > -----END PGP SIGNATURE----- The reason I picked 6 was because the last set of changes to nullfs added *3*, so I figure hedging 2x that is a good bet. Also prime numbers hash better so why not? :) About using arrays, arrays are slower than direct member access because of compiler issues so .. ...if you are still reading this sentence I am joking. :) Sure, I'll switch to an array. -- Alfred Perlstein