RFC: slow-down option

[Christoph Biedl]

Joe wrote...

> This is way beyond my level of expertise, but wouldn't something like
> ionice help with that?

Although I'm not Marian, probably not. The ionice program does a
reasonable good job when it's about prioritizing read operation. The
context makes me guess it's rather about writing.

> Also, check out:
> 
> 2 more pipe utilities
> 
> Viewer & throttle
> http://www.ivarch.com/programs/pv.shtml
> 
> Throttle - limits bandwidth of a pipe - for use with network transfers
> http://linux.die.net/man/1/throttle

The pv utility is way to little known and served me well in many
situations, and throttle seems to do quite the same. Both however seem
to do quite the same thing rsync's --bwlimit option does, while the
latter is more sophisticated.

It the issue is the one I have in mind (which is one I constantly
suffer from), the actual problem is the dirty buffer writeback
strategy, deep in the Linux kernel.

    Christoph