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From: Charles Henrich <henrich@crh.cl.msu.edu>
Message-Id: <199701041902.OAA05751@crh.cl.msu.edu>
Subject: Re: Metadata updated every 30 seconds?
To: dg@root.com
Date: Sat, 4 Jan 1997 14:02:55 -0500 (EST)
Cc: freebsd-questions@FreeBSD.ORG
In-Reply-To: <199701040901.BAA24189@root.com> from David Greenman at "Jan 4, 97 01:01:36 am"
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>2) To write out modified inodes. In this case, the writes are delayed to give
>   the system time to modify/update as many inodes within an inode block
>   (there are usually 64 inodes per 8K block), or update the block pointers
>   in the indirect blocks, without having to do a write for every one. The
>   alternative would be to do a write of the 8K inode block every time a file
>   was accessed (to update the file access time), and write out an 8K indirect
>   block every time a new block was allocated to the file. This would be VERY
>   slow.

Right, but in the case of a news spool, with noatime set, files are very very
rarely ever modified, they are only created and read.  (lack of knowledge
warning!) Im assuming that the inode data for a new inode is also written out
at update time, if they werent you wouldnt gain anything by doing sync()'s
every 30 seconds except for some stability (which frankly on a news spool im
not terribly worried about, at about 2-3GB/day my spool fills up rather fast :)

-Crh

       Charles Henrich     Michigan State University     henrich@msu.edu

                         http://pilot.msu.edu/~henrich