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Date: Mon, 20 Mar 1995 22:14:40 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199503201214.WAA16945@godzilla.zeta.org.au>
To: davidg@Root.COM, nate@sneezy.sri.com
Subject: Re: cvs commit: src/sys/ufs/ffs ffs_vfsops.c
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>>> >>   Modified:    sys/ufs/ffs ffs_vfsops.c
>>> >>   Log:
>>> >>   Don't sync the inode date changes of character special devices
>>> >>   during the FS sync. The system would appear to hang momentarily
>>> >>   if there was a large backlog of I/O.

>   Sorry, I was in a bad mood yesterday morning. Yes, I have every reason to
>believe that this is the one and only cause of the multi-second hangs that
>people noticed under certain circumstances. I was easily able to reproduce the
>problem by carefully choosing what was being written to a file. disksort()
>was cooperating in the problem by defering the write of the character device
>inode by as much as 8 seconds in the contrived tests I was doing. The change

Perhaps this was why tty buffer overflows for uucp were so common.

Bruce