Re: strange disk activity [tail -f]

Zefram (A.Main@dcs.warwick.ac.uk)
Mon, 1 Apr 1996 12:45:45 +0100 (BST)


>yep, "tail -f" reads (polls) the file every second, this in turn changes
>the atime field, and bdflush updates the inode and the superblock.

There's a voice in my head saying "that should happen on open(2), not
read(2)". Am I just hallucinating? More to the point, why do we get
this repeated (and annoying) disk activity under 1.3.~80 but not
1.2.x? Can the new bdflush be tuned to wait longer before flushing,
and if so, how?

>might be a stupid question, but is there no way doing event based reads
>on files [selects and/or blocking reads at the end of the file] ?

Not under Unix.

-zefram