On Tue, Sep 22, 2020 at 5:51 PM Chris Down <chris@xxxxxxxxxxxxxx> wrote: > > Chunxin Zang writes: > >My usecase is that there are two types of services in one server. They > >have difference > >priorities. Type_A has the highest priority, we need to ensure it's > >schedule latency、I/O > >latency、memory enough. Type_B has the lowest priority, we expect it > >will not affect > >Type_A when executed. > >So Type_A could use memory without any limit. Type_B could use memory > >only when the > >memory is absolutely sufficient. But we cannot estimate how much > >memory Type_B should > >use. Because everything is dynamic. So we can't set Type_B's memory.high. > > > >So we want to release the memory of Type_B when global memory is > >insufficient in order > >to ensure the quality of service of Type_A . In the past, we used the > >'force_empty' interface > >of cgroup v1. > > This sounds like a perfect use case for memory.low on Type_A, and it's pretty > much exactly what we invented it for. What's the problem with that? But we cannot estimate how much memory Type_A uses at least. For example: total memory: 100G At the beginning, Type_A was in an idle state, and it only used 10G of memory. The load is very low. We want to run Type_B to avoid wasting machine resources. When Type_B runs for a while, it used 80G of memory. At this time Type_A is busy, it needs more memory. Usually we will reclaim the memory of B first for Type_A . If not enough, we will kill Type_B.
