On 12/06/2010 04:33 PM, Stroller wrote:
On 27/11/2010, at 10:22pm, Nikos Chantziaras wrote:
...
Does using the ck-sources kernel reduce the necessity to use ionice?
To some degree, yes.
Tried this late last week. You chose your words perfectly - there is only some
degree of improvement.
The machine seems much snappier if I return to an interactive session after
leaving it idle for some time, but during DVD rips it is still unresponsive for
tens of seconds at a time. It seems like maybe it responds quicker than
mainline sources, but it's still so slow that it's both unusable and hard to be
sure whether that's the case.
Will try cgroups this week, perhaps.
cgroups will not help with that either. I bet the problem is that the
kernel doesn't care about what kind of data it is caching. I came
across this on LKML, but no one was interested in a solution.
The problem is that the kernel caches all data. Ripping a DVD will
consume 4GB cache, and all other data will be thrown out. Throwing that
all out again after the rip has finished is an awful lot of I/O load.
The smart thing to do would be for the kernel to not cache such stuff
(DVD rips, big video files, etc.) But it does.
