From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: References: <20101115032531.GB27578@opal.ai.ki> <20101115051625.GD27578@opal.ai.ki> Date: Mon, 15 Nov 2010 15:37:56 +0000 Message-ID: From: roger peppe To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset=UTF-8 Subject: Re: [9fans] 9p vs http Topicbox-Message-UUID: 7ec4fad8-ead6-11e9-9d60-3106f5b1d025 On 15 November 2010 14:15, Gorka Guardiola wrote: > By namespaces I mean qid's , the notion that a file is the same if the > name isn't. mind you, that's problematic in 9p. the qid can be the same even if the file is different: % ls -lqd /n/dump/2006/0707/usr/rog (000000000003d540 1122 80) d-rwxr-xr-x M 42850 rog rog 0 Jun 7 2005 /n/dump/2005/0707/usr/rog % ls -lqd /n/dump/2006/0707/usr/rog (000000000003d540 1157 80) d-rwxr-xr-x M 42850 rog rog 0 Jun 12 2006 /n/dump/2006/0707/usr/rog they have the same qid but they're different directories with different contents. it's difficult to do a good job when embedding file systems, as the qid space is fixed. you can cheat, by rewriting the qid when the file is actually opened to paper over the most obvious problems, but it's still not great. perhaps things would be easier if qids were sufficiently large (e.g. sha1 hash sized) that an embedding file server could make up new qids (or create them by xoring in other info) without fear of clashes. re: 9p pipelining - i've been working on a little experiment related to this. i'll be sharing the results in a little while.