this will be called for every source frame  we might need to worry about sqrt  but i would need to profile  i will try comparing performance to versions that stub out sqrt  it s not much of an issue on my desktop  where the  total  cost to record the latency derived metrics is us  it s us on my pixel though  that includes re calculating a sqrt from n frames ago to subtract from the windowedanalyzer s accumulator  so there is sqrts total per source frame metrics sqrts all the sqrts currently use double precision  but i am pretty sure single precision would be good enough  in general  after getting the basics in place  i would like to switch the double precision math over to single precision where we can  if we really need to  we could use a sqrt approximation  as long as the approximation is monotonic  it should be good at tracking relative performance deltas even if the absolute value might be off a bit  if we really really need to  we could also remove smr  rms only needs to call sqrt on a reporting event  much less often  and not when a sample is added 