Re: [Patch 5/7] synchronous block I/O delays

Arjan van de Ven
2006-02-27T09:24:53Z

On Mon, 2006-02-27 at 04:13 -0500, Shailabh Nagar wrote:
> Arjan van de Ven wrote:
>
> >>+static inline void delayacct_blkio(void)
> >>+{
> >>+ if (unlikely(current->delays && delayacct_on))
> >>+ __delayacct_blkio();
> >>+}
> >>
> >>
> >
> >why is this unlikely?
> >
> >
> delayacct_on is expected to be off most of the time, hence the compound is
> unlikely too.

ok that opens the question: why is this a runtime tunable?
Is it really worth all this complexity?