From owner-freebsd-questions Tue Jan 3 14:01:11 1995 Return-Path: questions-owner Received: (from root@localhost) by freefall.cdrom.com (8.6.9/8.6.6) id OAA29942 for questions-outgoing; Tue, 3 Jan 1995 14:01:11 -0800 Received: from godzilla.zeta.org.au (godzilla.zeta.org.au [203.2.228.34]) by freefall.cdrom.com (8.6.9/8.6.6) with ESMTP id OAA29933; Tue, 3 Jan 1995 14:01:01 -0800 Received: (from bde@localhost) by godzilla.zeta.org.au (8.6.9/8.6.9) id IAA13647; Wed, 4 Jan 1995 08:57:02 +1100 Date: Wed, 4 Jan 1995 08:57:02 +1100 From: Bruce Evans Message-Id: <199501032157.IAA13647@godzilla.zeta.org.au> To: bde@zeta.org.au, terry@cs.weber.edu Subject: Re: Why does ls report wrong creation date on symlinks? Cc: crtb@upcoming.dcrt.nih.gov, freebsd-bugs@freebsd.org, freebsd-questions@freebsd.org Sender: questions-owner@freebsd.org Precedence: bulk > [slowness of find and ls caused by having to update directory access times] >> I think this problem should be handled by caching the access time stamps >> or even by storing them outside of inodes. The timestamps for all >> directories can be cached in a tiny amount of memory on most systems. >> (E.g., my 426MB usr partition has only 1932 directories so the access >> times could be cached in only 8K or 16K.) This memory could be written >> to disk very rarely (e.g., only when the fs is unmounted. POSIX doesn't >> require timestamps to be preserved if the system panics ;-). >This is somewhat of a non-sequitor. Typically "marked for update" is >a euphamism for blowing the date information in the in core inode, then >marking the inode as dirty meta-data by setting a vnode flag. In Minix, reading the current time is very inefficient (it requires sending a message to another task and waiting for the reply), so timestamping is implemented by just setting a vnode flag for the "marking" step and not updating the file times until a close(), stat(), fstat() or sync(). This method isn't typical but it is exactly what is described in POSIX 2.3.5. >... >Well, I got carried away again... 8-). Time to move off to the file >system list? Yes. I almost moved it a couple of replies ago. Bruce