Re: [PATCH 00/23] per device dirty throttling -v8

[Ingo Molnar]

* Diego Calleja <diegocg@xxxxxxxxx> wrote:

> > Measurements show that noatime helps 20-30% on regular desktop 
> > workloads, easily 50% for kernel builds and much more than that (in 
> > excess of 100%) for file-read-intense workloads. We cannot just walk
> 
> And as everybody knows in servers is a popular practice to disable it. 
> According to an interview to the kernel.org admins....

yeah - but i'd be surprised if more than 1% of all Linux servers out 
there had noatime.

> "Beyond that, Peter noted, "very little fancy is going on, and that is 
> good because fancy is hard to maintain." He explained that the only 
> fancy thing being done is that all filesystems are mounted noatime 
> meaning that the system doesn't have to make writes to the filesystem 
> for files which are simply being read, "that cut the load average in 
> half."

nice quote :-)

> I bet that some people would consider such performance hit a bug...

yeah.

	Ingo
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