> Its time cost is about 800 nanoseconds on a 2C/4T platform and > 2~3 microseconds on a 2S/36C/72T server in normal case, and in > worst case where vm_committed_as's spinlock is under severe > contention, it costs 30~40 microseconds for the 2S/36C/72T sever, This will be likely 40-80us on larger systems, although the overhead is often non linear so it might get worse. > which should be fine for its only two users: /proc/meminfo and > HyperV balloon driver's status trace per second. There are some setups who do frequent sampling of /proc/meminfo in the background. Increased overhead could be a problem for them. But not proposing a change now. If someone complains have to revisit I guess, perhaps adding a rate limit of some sort. -Andi
