Re: Linux 2.6.29

On Thu, 26 Mar 2009, Andrew Morton wrote:
> 
> Why does everyone just sit around waiting for the kernel to put a new
> value into two magic numbers which userspace scripts could have set?
> 
> My /etc/rc.local has been tweaking dirty_ratio, dirty_background_ratio
> and swappiness for many years.  I guess I'm just incredibly advanced.

.. and as a result you're also testing something that nobody else is.

Look at the complaints from people about fsync behavior that Ted says he 
cannot see. Let me guess: it's because Ted probably has tweaked his 
environment, because he is advanced. As a result, other people see 
problems, he does not.

That's not "advanced". That's totally f*cking broken.

Having different distributions tweak all those tweakables is just even 
_more_ so. It's the anti-thesis of "advanced". It's just stupid.

We should aim to get it right. The "user space can tweak any numbers they 
want" is ALWAYS THE WRONG ANSWER. It's a cop-out, but more importantly, 
it's a cop-out that doesn't even work, and that just results in everybody 
having different setups. Then nobody is happy.

		Linus