Paul Menage wrote: > On 10/4/07, Balbir Singh <balbir@xxxxxxxxxxxxxxxxxx> wrote: >> Paul Menage wrote: >>> On 10/4/07, Balbir Singh <balbir@xxxxxxxxxxxxxxxxxx> wrote: >>>> Forbidding writing to the root resource counter is a policy decision >>>> I am unable to make up my mind about. It sounds right, but unless >>>> we have a notion of unlimited resources, I am a bit concerned about >>>> taking away this flexibility. >>> One big reason for doing this is to make virtualization easier - if >>> you expect not to be able to write to your root cgroup's limits files, >>> then it's easier to make them non-writeable for a virtual server. >>> >> Can't we handle that through file system permissions? virtual servers >> will not run as root > > They'll probably run as root in their own user namespace if at all. > But that's the point - if userspace in general expects root cgroup > limits to not be writeable (the same way that root cpusets > cpus/mems_allowed files aren't writeable) then virtual servers will > break less. > In that case, let's have a value that says RES_COUNTER_INFINITY and set the root to that value and make the root cgroup limits read-only. >> But system administrators deal with memory in MB and GB. When you go >> to buy memory, you don't specify, I need 1 << 30 or 2^30 bytes of >> memory :-). Most administrators track their memory using these >> quantifiers. > > OK, so maybe we should just fold a call to memparse() into > cgroup_write_uint? Then we could use the plain write_uint() method in > the control file? > Yes, either that way or add a strategy function, that would take the string input from the user and convert it to unsigned long long value. I am ok with either approach. >>>> Do read_uint() and write_uint(), just read and write unsigned >>>> integers? >>> Correct. >>> >> Oops.. that would be problem, what if I wanted to set my limit to >> unsigned long long max? > > Sorry, I wasn't getting your point about the sizing. No, they're u64 > values. (And I guess could be changed to unsigned long long if people > preferred). > I would prefer unsigned long long, but we could get more opinions. > Paul -- Warm Regards, Balbir Singh Linux Technology Center IBM, ISTL _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers