On Sat, May 21, 2022 at 07:37:36PM +0300, Vasily Averin wrote: > Creating each new cgroup allocates 4Kb for struct cgroup. This is the > largest memory allocation in this scenario and is epecially important > for small VMs with 1-2 CPUs. > > Common part of the cgroup creation: > Allocs Alloc $1*$2 Sum Allocation > number size > -------------------------------------------- > 16 ~ 352 5632 5632 KERNFS > 1 + 4096 4096 9728 (cgroup_mkdir+0xe4) > 1 584 584 10312 (radix_tree_node_alloc.constprop.0+0x89) > 1 192 192 10504 (__d_alloc+0x29) > 2 72 144 10648 (avc_alloc_node+0x27) > 2 64 128 10776 (percpu_ref_init+0x6a) > 1 64 64 10840 (memcg_list_lru_alloc+0x21a) > percpu: > 1 + 192 192 192 call_site=psi_cgroup_alloc+0x1e > 1 + 96 96 288 call_site=cgroup_rstat_init+0x5f > 2 12 24 312 call_site=percpu_ref_init+0x23 > 1 6 6 318 call_site=__percpu_counter_init+0x22 > > '+' -- to be accounted, > '~' -- partially accounted > > Accounting of this memory helps to avoid misuse inside memcg-limited > containers. > > Signed-off-by: Vasily Averin <vvs@xxxxxxxxxx> Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>
