Paul Menage wrote: > On 8/5/06, Srivatsa Vaddagiri <[EMAIL PROTECTED]> wrote: > >> >> The other useful statistics (which is kind of inverse of this) is to know >> the "blocking" time on runqueue for different tasks. This other >> statistics >> should be available already in recent kernels (as part of delaystats >> feature) and is exported to user-space over netlink interface (which >> should be less expensive compared to /proc). > > > I took a look at that - as far as I could see, the interface is > restricted to "tell me the stats for pid X now" and "send me stats > whenever a process exits". Neither of those provide the kind of > aggregation/tracking support that you can easily get with resource > groups.
I think people are talking about different things here that could do with some clarification: - delay accounting: measures how long X had to wait to get cpu time. Currently X is pid/tgid but in future, it *could* be extended to an RG's wait for cpu (which was Vatsa's point I think), but thats going to be costly if one wants it to be accurate and available continuously. - taskstats interface: used only by delay accounting currently and is inherently a per-tid/tgid interface. As Paul rightly points out, it has nothing to offer for accounting of aggregates and that is not going to change even in future (it would be better to export per-RG delays over whatever interface RG exports). So RG is the right infrastructure for what he's proposing. FWIW, I don't think this accounting-only controller will strengthen the case for RG (or RG-like infrastructure) much because we need atleast one of CPU or memory controllers (or so we've been told). That said, there doesn't seem to be any harm in carrying it along with the numtasks controller as one of the useful things RG infrastructure can facilitate. Utility of this accounting resource controller isn't in doubt. --Shailabh ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ ckrm-tech mailing list https://lists.sourceforge.net/lists/listinfo/ckrm-tech
