On 11/26/2010 05:57 PM, Stroller wrote:
Hi there,
As per subject, what's the best way to improve interactivity with
heavy disk activity, please?
Or perhaps a better question would be: what approaches are
available?
[...]
But I have also heard of `ionice` in the past:
http://linux.die.net/man/1/ionice
I've never used that - in fact, I can't recall ever having to use the
regular `nice` - but I think maybe I should consider it.
'nice' is for CPU time. 'ionice' is for disk I/O time. So yes, it
helps a lot with heavy disk tasks if you run them -c3. This is why
Portage has support for ionice (PORTAGE_IONICE_COMMAND). There's also
'schedtool' (sys-process/schedtool).
The way I solved the I/O problems is to use the sys-kernel/ck-sources
kernel (2.6.36-r3). It shouldn't be necessary to use ionice and
schedtool for most tasks, but I use it for portage with this in make.conf:
PORTAGE_NICENESS=19
PORTAGE_IONICE_COMMAND="sh -c \"schedtool -D \${PID}; ionice -c 3 -p
\${PID}\""
But you can use this method for everything you want. Running something
with nice -19, ionice -c3 and schedtool -D should make it pretty much
invisible; it should have zero impact on interactivity. At least that's
the case here when using sys-kernel/ck-sources.
