From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=5.0 tests=MAILING_LIST_MULTI autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 9827 invoked from network); 30 Dec 2021 03:45:44 -0000 Received: from minnie.tuhs.org (45.79.103.53) by inbox.vuxu.org with ESMTPUTF8; 30 Dec 2021 03:45:44 -0000 Received: by minnie.tuhs.org (Postfix, from userid 112) id BA0A59CFF5; Thu, 30 Dec 2021 13:45:41 +1000 (AEST) Received: from minnie.tuhs.org (localhost [127.0.0.1]) by minnie.tuhs.org (Postfix) with ESMTP id 262419CD62; Thu, 30 Dec 2021 13:45:17 +1000 (AEST) Received: by minnie.tuhs.org (Postfix, from userid 112) id B4A0F9CD62; Thu, 30 Dec 2021 13:45:15 +1000 (AEST) Received: from mercury.lcs.mit.edu (mercury.lcs.mit.edu [18.26.0.122]) by minnie.tuhs.org (Postfix) with ESMTPS id AEB939CC2E for ; Thu, 30 Dec 2021 13:45:13 +1000 (AEST) Received: by mercury.lcs.mit.edu (Postfix, from userid 11178) id B9B3718C08E; Wed, 29 Dec 2021 22:45:12 -0500 (EST) To: tuhs@minnie.tuhs.org Message-Id: <20211230034512.B9B3718C08E@mercury.lcs.mit.edu> Date: Wed, 29 Dec 2021 22:45:12 -0500 (EST) From: jnc@mercury.lcs.mit.edu (Noel Chiappa) Subject: Re: [TUHS] moving directories in svr2 X-BeenThere: tuhs@minnie.tuhs.org X-Mailman-Version: 2.1.26 Precedence: list List-Id: The Unix Heritage Society mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: jnc@mercury.lcs.mit.edu Errors-To: tuhs-bounces@minnie.tuhs.org Sender: "TUHS" > From: Bakul Shah > My guess is *not* storing a path instead of a ptr to the inode was done > to save on memory. More probably speed; those old disks were not fast, and on a PDP-11, disk caches were so small that converting the path to the current directory to its in memory inode could take a bunch of disk reads. > Every inode has a linkcount so detecting when the last conn. is severed > not a problem. Depends; if a directory _has_ to be empty before it can be deleted, maybe; but if not, no. (Consider if /a/b/c/d exists, and /a/b is removed; the tree underneath it has to be walked and the components deleted. That could take a while...) In the general case (e.g. without the restriction to a tree), it's basically the same problem as garbage collection in LISP. Noel