summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorGravatar Joey Hess <joeyh@joeyh.name>2016-11-21 20:56:58 -0400
committerGravatar Joey Hess <joeyh@joeyh.name>2016-11-21 20:56:58 -0400
commitf0f7e900cc9248c05314eaed418317de690a24d8 (patch)
tree75fc603169b6639ce553f151b25233be3c8e9f2f
parent42c6d2727d46c6bead3684965bccb83728bcd09d (diff)
try to gather scattered writes
git upload-pack makes some uncessary writes in sequence, this tries to gather them together to avoid needing to send multiple DATA packets when just one will do. In a small pull, this reduces the average number of DATA packets from 4.5 to 2.5.
-rw-r--r--Remote/Helper/P2P/IO.hs34
1 files changed, 28 insertions, 6 deletions
diff --git a/Remote/Helper/P2P/IO.hs b/Remote/Helper/P2P/IO.hs
index b3597abf9..dd0b9631d 100644
--- a/Remote/Helper/P2P/IO.hs
+++ b/Remote/Helper/P2P/IO.hs
@@ -5,7 +5,7 @@
- Licensed under the GNU GPL version 3 or higher.
-}
-{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE RankNTypes, CPP #-}
module Remote.Helper.P2P.IO
( RunProto
@@ -179,9 +179,31 @@ relayReader :: MVar RelayData -> Handle -> IO ()
relayReader v hout = loop
where
loop = do
- b <- B.hGetSome hout 65536
- if B.null b
- then return ()
- else do
- putMVar v $ RelayToPeer (L.fromChunks [b])
+ bs <- getsome []
+ case bs of
+ [] -> return ()
+ _ -> do
+ putMVar v $ RelayToPeer (L.fromChunks bs)
loop
+
+ -- Waiit for the first available chunk. Then, without blocking,
+ -- try to get more chunks, in case a stream of chunks is being
+ -- written in close succession.
+ --
+ -- On Windows, hGetNonBlocking is broken, so avoid using it there.
+ getsome [] = do
+ b <- B.hGetSome hout chunk
+ if B.null b
+ then return []
+#ifndef mingw32_HOST_OS
+ else getsome [b]
+#else
+ else return [b]
+#endif
+ getsome bs = do
+ b <- B.hGetNonBlocking hout chunk
+ if B.null b
+ then return (reverse bs)
+ else getsome (b:bs)
+
+ chunk = 65536