Re: io priorities?

[Sebastian Kuzminsky <seb@highlab.com>]

Andrew Morton <akpm@osdl.org> wrote:
] "Richard B. Johnson" <root@chaos.analogic.com> wrote:
] > Periodically fsync() the logs so there isn't soooo much stuff to
] > write. In fact, a simple sync() call about once every few seconds
] > should make everything work,
] 
] Yup.  Alternatively, set /proc/sys/vm/dirty_ratio and /proc/sys/vm/dirty_background_ratio
] to really small values.  Say, 2 and 1.


Thanks guys, that sort of fixes it, but not really.  Occasionally i get
a big load of IO (copying tens of megs of log files around), and even if
i synced a second before, now there's tens of seconds of IO in the queue,
and my next fsync() still drags on.


Really i just want this one process to go to the front of the queue, any
time it has IO to do, independent of what the rest of the system is doing.




--
Sebastian