From 8c12c6939aab9106db14ec2d11d983bc5b29fb2c Mon Sep 17 00:00:00 2001
From: Niall Sheridan <nsheridan@gmail.com>
Date: Sun, 7 Jul 2019 21:33:44 +0100
Subject: Switch to modules

---
 .../grpc/internal/transport/bdp_estimator.go       | 140 ---------------------
 1 file changed, 140 deletions(-)
 delete mode 100644 vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go

(limited to 'vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go')

diff --git a/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go b/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go
deleted file mode 100644
index 63cd262..0000000
--- a/vendor/google.golang.org/grpc/internal/transport/bdp_estimator.go
+++ /dev/null
@@ -1,140 +0,0 @@
-/*
- *
- * Copyright 2017 gRPC authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
-package transport
-
-import (
-	"sync"
-	"time"
-)
-
-const (
-	// bdpLimit is the maximum value the flow control windows
-	// will be increased to.
-	bdpLimit = (1 << 20) * 4
-	// alpha is a constant factor used to keep a moving average
-	// of RTTs.
-	alpha = 0.9
-	// If the current bdp sample is greater than or equal to
-	// our beta * our estimated bdp and the current bandwidth
-	// sample is the maximum bandwidth observed so far, we
-	// increase our bbp estimate by a factor of gamma.
-	beta = 0.66
-	// To put our bdp to be smaller than or equal to twice the real BDP,
-	// we should multiply our current sample with 4/3, however to round things out
-	// we use 2 as the multiplication factor.
-	gamma = 2
-)
-
-// Adding arbitrary data to ping so that its ack can be identified.
-// Easter-egg: what does the ping message say?
-var bdpPing = &ping{data: [8]byte{2, 4, 16, 16, 9, 14, 7, 7}}
-
-type bdpEstimator struct {
-	// sentAt is the time when the ping was sent.
-	sentAt time.Time
-
-	mu sync.Mutex
-	// bdp is the current bdp estimate.
-	bdp uint32
-	// sample is the number of bytes received in one measurement cycle.
-	sample uint32
-	// bwMax is the maximum bandwidth noted so far (bytes/sec).
-	bwMax float64
-	// bool to keep track of the beginning of a new measurement cycle.
-	isSent bool
-	// Callback to update the window sizes.
-	updateFlowControl func(n uint32)
-	// sampleCount is the number of samples taken so far.
-	sampleCount uint64
-	// round trip time (seconds)
-	rtt float64
-}
-
-// timesnap registers the time bdp ping was sent out so that
-// network rtt can be calculated when its ack is received.
-// It is called (by controller) when the bdpPing is
-// being written on the wire.
-func (b *bdpEstimator) timesnap(d [8]byte) {
-	if bdpPing.data != d {
-		return
-	}
-	b.sentAt = time.Now()
-}
-
-// add adds bytes to the current sample for calculating bdp.
-// It returns true only if a ping must be sent. This can be used
-// by the caller (handleData) to make decision about batching
-// a window update with it.
-func (b *bdpEstimator) add(n uint32) bool {
-	b.mu.Lock()
-	defer b.mu.Unlock()
-	if b.bdp == bdpLimit {
-		return false
-	}
-	if !b.isSent {
-		b.isSent = true
-		b.sample = n
-		b.sentAt = time.Time{}
-		b.sampleCount++
-		return true
-	}
-	b.sample += n
-	return false
-}
-
-// calculate is called when an ack for a bdp ping is received.
-// Here we calculate the current bdp and bandwidth sample and
-// decide if the flow control windows should go up.
-func (b *bdpEstimator) calculate(d [8]byte) {
-	// Check if the ping acked for was the bdp ping.
-	if bdpPing.data != d {
-		return
-	}
-	b.mu.Lock()
-	rttSample := time.Since(b.sentAt).Seconds()
-	if b.sampleCount < 10 {
-		// Bootstrap rtt with an average of first 10 rtt samples.
-		b.rtt += (rttSample - b.rtt) / float64(b.sampleCount)
-	} else {
-		// Heed to the recent past more.
-		b.rtt += (rttSample - b.rtt) * float64(alpha)
-	}
-	b.isSent = false
-	// The number of bytes accumulated so far in the sample is smaller
-	// than or equal to 1.5 times the real BDP on a saturated connection.
-	bwCurrent := float64(b.sample) / (b.rtt * float64(1.5))
-	if bwCurrent > b.bwMax {
-		b.bwMax = bwCurrent
-	}
-	// If the current sample (which is smaller than or equal to the 1.5 times the real BDP) is
-	// greater than or equal to 2/3rd our perceived bdp AND this is the maximum bandwidth seen so far, we
-	// should update our perception of the network BDP.
-	if float64(b.sample) >= beta*float64(b.bdp) && bwCurrent == b.bwMax && b.bdp != bdpLimit {
-		sampleFloat := float64(b.sample)
-		b.bdp = uint32(gamma * sampleFloat)
-		if b.bdp > bdpLimit {
-			b.bdp = bdpLimit
-		}
-		bdp := b.bdp
-		b.mu.Unlock()
-		b.updateFlowControl(bdp)
-		return
-	}
-	b.mu.Unlock()
-}
-- 
cgit v1.2.3