Richard Henderson <r...@twiddle.net> writes: > On 09/05/2017 05:33 PM, Pranith Kumar wrote: >>> This significantly degrades performance of alpha-softmmu. >>> It spends about 25% of all cpu time in memset. >> >> What workload does it degrade for? I will try to reproduce and see >> which memset is causing this. > > emerge --update --ask @world > > which is a lot of python, iirc. > > It is the tlb flush memset that is causing this. > The tlb has grown from a few kB to 300kB with your patch.
Hmm I wonder if this is QEMU doing global flushes which could actually be partial TLB flushes? emerge is quite a memory hog though so its conceivable we are generating a lot of churn as it runs. -- Alex Bennée
