Date: Fri, 22 Aug 2008 17:46:31 +0200 From: Luigi Rizzo <rizzo@iet.unipi.it> To: Brooks Davis <brooks@freebsd.org> Cc: Ivan Voras <ivoras@freebsd.org>, Christian Brueffer <brueffer@freebsd.org>, freebsd-arch@freebsd.org Subject: Re: Magic symlinks redux Message-ID: <20080822154631.GA61495@onelab2.iet.unipi.it> In-Reply-To: <20080822150728.GB57443@lor.one-eyed-alien.net> References: <g8kv7v$sp2$1@ger.gmane.org> <20080822090448.GB57441@onelab2.iet.unipi.it> <48AE89DC.9080408@yandex.ru> <g8m458$d3$1@ger.gmane.org> <20080822120525.GA1366@haakonia.hitnet.RWTH-Aachen.DE> <20080822145616.GA61094@onelab2.iet.unipi.it> <20080822150728.GB57443@lor.one-eyed-alien.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, Aug 22, 2008 at 10:07:29AM -0500, Brooks Davis wrote: > On Fri, Aug 22, 2008 at 04:56:16PM +0200, Luigi Rizzo wrote: > > On Fri, Aug 22, 2008 at 02:05:26PM +0200, Christian Brueffer wrote: > > > On Fri, Aug 22, 2008 at 12:24:41PM +0200, Ivan Voras wrote: > > ... > > > > This patch is huge. As far as I can tell DragonflyBSD has a whole > > > > framework dedicated to varsyms, spread across a fair part of the kernel > > > > and with at least one special userland utility. It allows the operator > > > > to define his own variables that can be used in the substitutions, and I > > > > don't see that it predefines "special" variables like "uid" and > > > > "hostname". It's not necessarily a bad solution but I consider it overkill. > > ... > > > Brooks has a varsym port in p4, see //depot/user/brooks/varsym/ > > > > this also seems to be based on Dragonfly's code, quite intrusive. > > This code adds one global symbol, one function call in the vfs code, > and two pointers to struct proc. For that we get a system which is > significantly more flexible than the NetBSD code. > > While the simplicity of the NetBSD code is somewhat attractive, the > fact that variables can not be defined renders it useless for my > purposes which are providing partial file system virtulization for > computing job/sessions where I need to key off of externally derived job > IDs or job specific temporary paths. understood -- it's just that the difference in code size is impressive. Do you know how much of it is used to implement the "varsym" subsystem (user- or system-wide variables) and how much is the core name translation ? cheers luigi
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20080822154631.GA61495>