Re: spinlock efficiency problem [was 2.5.57 IO slowdown with CONFIG_PREEMPT enabled)

Alan
2003-01-21T05:01:23Z

On Mon, 2003-01-20 at 22:58, Joe Korty wrote:
> The new, preemptable spin_lock() spins on an atomic bus-locking
> read/write instead of an ordinary read, as the original spin_lock
> implementation did. Perhaps that is the source of the inefficiency
> being seen.

Its a fairly critical "Never do this" on older intel processors and
kills the box very efficiently so your diagnosis is extremely
plausible