Date: Tue, 21 Nov 2017 17:08:16 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 223786] Remounting a UFS filesystem read-only takes very long time Message-ID: <bug-223786-8@https.bugs.freebsd.org/bugzilla/>
next in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D223786 Bug ID: 223786 Summary: Remounting a UFS filesystem read-only takes very long time Product: Base System Version: 10.4-STABLE Hardware: Any OS: Any Status: New Keywords: regression Severity: Affects Only Me Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: mi@ALDAN.algebra.com I usually keep my / mounted read-only -- mostly for safety. When I need to change some aspect of configuration or add a port, I remount rw, do what ne= eds doing, and then remount back to read-only mode. This worked for me for many years, but lately I noticed, the remounting bac= k to the ro-mode is taking longer than it used to. Many seconds, especially, whe= n it was active shortly before the remount command. Today, however, with the freshly rebuilt kernel (FreeBSD 10.4-STABLE #15 r325999M), it takes well over a minute! A minute, during which the machine largely freezes -- for example, making new logins impossible. I understand the need to flush the unwritten to disk, when switching to ro,= but just how much should that take in the scenario I just had: 1048 11:56 mount -orw -u / 1049 11:56 chmod u+s /opt/cyrus/bin/deliver 1050 11:56 mount -oro -u / ? The second remount took well over minute and it seems wrong. The filesystem is based on SSD and looks like: /dev/ada0s1a on / (ufs, NFS exported, local, read-only) `tunefs -p /` reports: tunefs: POSIX.1e ACLs: (-a) disabled tunefs: NFSv4 ACLs: (-N) disabled tunefs: MAC multilabel: (-l) disabled tunefs: soft updates: (-n) enabled tunefs: soft update journaling: (-j) disabled tunefs: gjournal: (-J) disabled tunefs: trim: (-t) enabled tunefs: maximum blocks per file in a cylinder group: (-e) 1048576 tunefs: average file size: (-f) 16384 tunefs: average number of files in a directory: (-s) 64 tunefs: minimum percentage of free space: (-m) 8% tunefs: space to hold for metadata blocks: (-k) 0 tunefs: optimization preference: (-o) time tunefs: volume label: (-L) --=20 You are receiving this mail because: You are the assignee for the bug.=
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-223786-8>