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<p class="MsoNormal">Parav presented his recent patch-set that adds RDMA cgroup support.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Controlling RDMA resources in general (without device affinity) is simpler to implement and administer, as this scheme does not need to handle HW hot plug/unplug situations.<o:p></o:p></p>
<p class="MsoNormal">However, controlling resources per-device is more meaningful since the resources themselves are per-device.<o:p></o:p></p>
<p class="MsoNormal">So, the general scheme holds well when a single device is used, but in the general case, a per-device scheme seems better.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Another approach to consider: use the general scheme as the interface, but apply it on a per-device basis.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The question of whether controlling resources per-port is reasonable. However, it seems that this doesn’t add any further control because in multi-port devices, resources are not restricted to specific ports.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It was generally preferred that RDMA resources should have a distinct cgroup.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The notion of soft limits was discussed. However, it seems that there is no natural definition for this, since HW resources are not migrated on demand between processes.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regarding abstractions, Verbs objects are a good candidate for granular per-resource tracking.<o:p></o:p></p>
<p class="MsoNormal">Even for devices that don’t have HW limits for specific resources – the name-space itself could be controlled.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">More abstract notions could be considered, such as device “resource pools”.<o:p></o:p></p>
<p class="MsoNormal">Providers can control their actual HW resources more precisely, but it is not clear to the user what is actually controlled.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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