Vakul Garg <vakul.g...@nxp.com> wrote: > Post kernel 4.9, I am experiencing more than 50% degrade in ipsec performance > on my arm64 based systems (with onchip crypto accelerator). > (We use only lts kernels). My understanding is that it is mainly due to xfrm > flow cache removal in version 4.12.
Yes, likely. > I am not sure whether any subsequent work could recover the lost performance. > With kernel 4.19, I see that xfrm_state_find() is taking a lot of cpu (more > than 15%). Can you share details about the setup? I.e., how many policies, states etc.? Do you use xfrm interfaces? > Further, perf show that a lot of atomic primitives such as > __ll_sc___cmpxchg_case_mb_4(), > __ll_sc_atomic_sub_return() are being invoked. On 16 core system, they > consume more than 30% of cpu. Thats not good, perhaps we should look at pcpu refcounts for the xfrm state structs.
