Re: [resend][PATCH 2/4] Revert "oom: deprecate oom_adj tunable"

From: David Rientjes
Date: Sun Nov 14 2010 - 16:39:39 EST


On Sun, 14 Nov 2010, KOSAKI Motohiro wrote:

> No irrelevant. Your patch break their environment even though
> they don't use oom_adj explicitly. because their application are using it.
>

The _only_ difference too oom_adj since the rewrite is that it is now
mapped on a linear scale rather than an exponential scale. That's because
the heuristic itself has a defined range [0, 1000] that characterizes the
memory usage of the application it is ranking. To show any breakge, you
would have to show how oom_adj values being used by applications are based
on a calculated value that prioritizes those tasks amongst each other.
With the exponential scale, that's nearly impossible because of the number
of arbitrary heuristics that were used before oom_adj were considered
(runtime, nice level, CAP_SYS_RAWIO, etc).

So don't talk about userspace breakage when you can't even describe it or
present a single usecase.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/