diff options
Diffstat (limited to 'Utility/Metered.hs')
| -rw-r--r-- | Utility/Metered.hs | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/Utility/Metered.hs b/Utility/Metered.hs index a7c9c37..8fd9c9b 100644 --- a/Utility/Metered.hs +++ b/Utility/Metered.hs @@ -37,6 +37,7 @@ module Utility.Metered ( demeterCommandEnv, avoidProgress, rateLimitMeterUpdate, + bwLimitMeterUpdate, Meter, mkMeter, setMeterTotalSize, @@ -51,6 +52,7 @@ import Utility.Percentage import Utility.DataUnits import Utility.HumanTime import Utility.SimpleProtocol as Proto +import Utility.ThreadScheduler import qualified Data.ByteString.Lazy as L import qualified Data.ByteString as S @@ -380,6 +382,46 @@ rateLimitMeterUpdate delta (Meter totalsizev _ _ _) meterupdate = do meterupdate n else putMVar lastupdate prev +-- | Bandwidth limiting by inserting a delay at the point that a meter is +-- updated. +-- +-- This will only work when the actions that use bandwidth are run in the +-- same process and thread as the call to the MeterUpdate. +-- +-- For example, if the desired bandwidth is 100kb/s, and over the past +-- 1/10th of a second, 30kb was sent, then the current bandwidth is +-- 300kb/s, 3x as fast as desired. So, after getting the next chunk, +-- pause for twice as long as it took to get it. +bwLimitMeterUpdate :: ByteSize -> Duration -> MeterUpdate -> IO MeterUpdate +bwLimitMeterUpdate bwlimit duration meterupdate + | bwlimit <= 0 = return meterupdate + | otherwise = do + nowtime <- getPOSIXTime + mv <- newMVar (nowtime, Nothing) + return (mu mv) + where + mu mv n@(BytesProcessed i) = do + endtime <- getPOSIXTime + (starttime, mprevi) <- takeMVar mv + + case mprevi of + Just previ -> do + let runtime = endtime - starttime + let currbw = fromIntegral (i - previ) / runtime + let pausescale = if currbw > bwlimit' + then (currbw / bwlimit') - 1 + else 0 + unboundDelay (floor (runtime * pausescale * msecs)) + Nothing -> return () + + meterupdate n + + nowtime <- getPOSIXTime + putMVar mv (nowtime, Just i) + + bwlimit' = fromIntegral (bwlimit * durationSeconds duration) + msecs = fromIntegral oneSecond + data Meter = Meter (MVar (Maybe TotalSize)) (MVar MeterState) (MVar String) DisplayMeter data MeterState = MeterState @@ -417,12 +459,14 @@ updateMeter (Meter totalsizev sv bv displaymeter) new = do -- | Display meter to a Handle. displayMeterHandle :: Handle -> RenderMeter -> DisplayMeter displayMeterHandle h rendermeter v msize old new = do + olds <- takeMVar v let s = rendermeter msize old new - olds <- swapMVar v s + let padding = replicate (length olds - length s) ' ' + let s' = s <> padding + putMVar v s' -- Avoid writing when the rendered meter has not changed. - when (olds /= s) $ do - let padding = replicate (length olds - length s) ' ' - hPutStr h ('\r':s ++ padding) + when (olds /= s') $ do + hPutStr h ('\r':s') hFlush h -- | Clear meter displayed by displayMeterHandle. May be called before |