Messages in this thread | | | Date | Sat, 4 Jan 2014 11:10:50 -0500 | From | Tejun Heo <> | Subject | Re: [PATCH 0/4] x86: Add Cache QoS Monitoring (CQM) support |
| |
Hello,
On Fri, Jan 03, 2014 at 12:34:41PM -0800, Peter P Waskiewicz Jr wrote: > The CPU features themselves are relatively straight-forward, but > the presentation of the data is less straight-forward. Since this > tracks cache usage and occupancy per process (by swapping Resource > Monitor IDs, or RMIDs, when processes are rescheduled), perf would > not be a good fit for this data, which does not report on a > per-process level. Therefore, a new cgroup subsystem, cacheqos, has > been added. This operates very similarly to the cpu and cpuacct > cgroup subsystems, where tasks can be grouped into sub-leaves of the > root-level cgroup.
I don't really understand why this is implemented as part of cgroup. There doesn't seem to be anything which requires cgroup. Wouldn't just doing it per-process make more sense? Even grouping would be better done along the traditional process hierarchy, no? And per-cgroup accounting can be trivially achieved from userland by just accumulating the stats according to the process's cgroup membership. What am I missing here?
Thanks.
-- tejun
| |