On 4/1/21 11:42 PM, Roman Gushchin wrote: > In our production experience the percpu memory allocator is sometimes struggling > with returning the memory to the system. A typical example is a creation of > several thousands memory cgroups (each has several chunks of the percpu data > used for vmstats, vmevents, ref counters etc). Deletion and complete releasing > of these cgroups doesn't always lead to a shrinkage of the percpu memory. > > The underlying problem is the fragmentation: to release an underlying chunk > all percpu allocations should be released first. The percpu allocator tends > to top up chunks to improve the utilization. It means new small-ish allocations > (e.g. percpu ref counters) are placed onto almost filled old-ish chunks, > effectively pinning them in memory. > > This patchset pretends to solve this problem by implementing a partial Really "pretends"? :) Or did you mean "attempts"?
