Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(1489)

Side by Side Diff: net/quic/congestion_control/cubic.h

Issue 683113005: Update from chromium https://crrev.com/302282 (Closed) Base URL: git@github.com:domokit/mojo.git@master
Patch Set: Created 6 years, 1 month ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View unified diff | Download patch
« no previous file with comments | « net/proxy/proxy_info_unittest.cc ('k') | net/quic/congestion_control/cubic.cc » ('j') | no next file with comments »
Toggle Intra-line Diffs ('i') | Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
OLDNEW
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be 2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file. 3 // found in the LICENSE file.
4 // 4 //
5 // Cubic algorithm, helper class to TCP cubic. 5 // Cubic algorithm, helper class to TCP cubic.
6 // For details see http://netsrv.csc.ncsu.edu/export/cubic_a_new_tcp_2008.pdf. 6 // For details see http://netsrv.csc.ncsu.edu/export/cubic_a_new_tcp_2008.pdf.
7 7
8 #ifndef NET_QUIC_CONGESTION_CONTROL_CUBIC_H_ 8 #ifndef NET_QUIC_CONGESTION_CONTROL_CUBIC_H_
9 #define NET_QUIC_CONGESTION_CONTROL_CUBIC_H_ 9 #define NET_QUIC_CONGESTION_CONTROL_CUBIC_H_
10 10
11 #include "base/basictypes.h" 11 #include "base/basictypes.h"
12 #include "net/base/net_export.h" 12 #include "net/base/net_export.h"
13 #include "net/quic/quic_bandwidth.h"
13 #include "net/quic/quic_clock.h" 14 #include "net/quic/quic_clock.h"
14 #include "net/quic/quic_connection_stats.h" 15 #include "net/quic/quic_connection_stats.h"
15 #include "net/quic/quic_time.h" 16 #include "net/quic/quic_time.h"
16 17
17 namespace net { 18 namespace net {
18 19
19 // TCP congestion window in QUIC is in packets, not bytes.
20 typedef uint32 QuicTcpCongestionWindow;
21
22 class NET_EXPORT_PRIVATE Cubic { 20 class NET_EXPORT_PRIVATE Cubic {
23 public: 21 public:
24 Cubic(const QuicClock* clock, QuicConnectionStats* stats); 22 Cubic(const QuicClock* clock, QuicConnectionStats* stats);
25 23
26 void SetNumConnections(int num_connections); 24 void SetNumConnections(int num_connections);
27 25
28 // Call after a timeout to reset the cubic state. 26 // Call after a timeout to reset the cubic state.
29 void Reset(); 27 void Reset();
30 28
31 // Compute a new congestion window to use after a loss event. 29 // Compute a new congestion window to use after a loss event.
32 // Returns the new congestion window in packets. The new congestion window is 30 // Returns the new congestion window in packets. The new congestion window is
33 // a multiplicative decrease of our current window. 31 // a multiplicative decrease of our current window.
34 QuicTcpCongestionWindow CongestionWindowAfterPacketLoss( 32 QuicPacketCount CongestionWindowAfterPacketLoss(QuicPacketCount current);
35 QuicTcpCongestionWindow current);
36 33
37 // Compute a new congestion window to use after a received ACK. 34 // Compute a new congestion window to use after a received ACK.
38 // Returns the new congestion window in packets. The new congestion window 35 // Returns the new congestion window in packets. The new congestion window
39 // follows a cubic function that depends on the time passed since last 36 // follows a cubic function that depends on the time passed since last
40 // packet loss. 37 // packet loss.
41 QuicTcpCongestionWindow CongestionWindowAfterAck( 38 QuicPacketCount CongestionWindowAfterAck(QuicPacketCount current,
42 QuicTcpCongestionWindow current, 39 QuicTime::Delta delay_min);
43 QuicTime::Delta delay_min);
44 40
45 private: 41 private:
46 static const QuicTime::Delta MaxCubicTimeInterval() { 42 static const QuicTime::Delta MaxCubicTimeInterval() {
47 return QuicTime::Delta::FromMilliseconds(30); 43 return QuicTime::Delta::FromMilliseconds(30);
48 } 44 }
49 45
50 // Compute the TCP Cubic alpha and beta based on the current number of 46 // Compute the TCP Cubic alpha and beta based on the current number of
51 // connections. 47 // connections.
52 float Alpha() const; 48 float Alpha() const;
53 float Beta() const; 49 float Beta() const;
54 50
55 // Update congestion control variables in QuicConnectionStats. 51 // Update congestion control variables in QuicConnectionStats.
56 void UpdateCongestionControlStats(QuicTcpCongestionWindow new_cubic_mode_cwnd, 52 void UpdateCongestionControlStats(QuicPacketCount new_cubic_mode_cwnd,
57 QuicTcpCongestionWindow new_reno_mode_cwnd); 53 QuicPacketCount new_reno_mode_cwnd);
58 const QuicClock* clock_; 54 const QuicClock* clock_;
59 55
60 // Number of connections to simulate. 56 // Number of connections to simulate.
61 int num_connections_; 57 int num_connections_;
62 58
63 // Time when this cycle started, after last loss event. 59 // Time when this cycle started, after last loss event.
64 QuicTime epoch_; 60 QuicTime epoch_;
65 61
66 // Time when we updated last_congestion_window. 62 // Time when we updated last_congestion_window.
67 QuicTime last_update_time_; 63 QuicTime last_update_time_;
68 64
69 // Last congestion window (in packets) used. 65 // Last congestion window (in packets) used.
70 QuicTcpCongestionWindow last_congestion_window_; 66 QuicPacketCount last_congestion_window_;
71 67
72 // Max congestion window (in packets) used just before last loss event. 68 // Max congestion window (in packets) used just before last loss event.
73 // Note: to improve fairness to other streams an additional back off is 69 // Note: to improve fairness to other streams an additional back off is
74 // applied to this value if the new value is below our latest value. 70 // applied to this value if the new value is below our latest value.
75 QuicTcpCongestionWindow last_max_congestion_window_; 71 QuicPacketCount last_max_congestion_window_;
76 72
77 // Number of acked packets since the cycle started (epoch). 73 // Number of acked packets since the cycle started (epoch).
78 uint32 acked_packets_count_; 74 uint32 acked_packets_count_;
79 75
80 // TCP Reno equivalent congestion window in packets. 76 // TCP Reno equivalent congestion window in packets.
81 QuicTcpCongestionWindow estimated_tcp_congestion_window_; 77 QuicPacketCount estimated_tcp_congestion_window_;
82 78
83 // Origin point of cubic function. 79 // Origin point of cubic function.
84 QuicTcpCongestionWindow origin_point_congestion_window_; 80 QuicPacketCount origin_point_congestion_window_;
85 81
86 // Time to origin point of cubic function in 2^10 fractions of a second. 82 // Time to origin point of cubic function in 2^10 fractions of a second.
87 uint32 time_to_origin_point_; 83 uint32 time_to_origin_point_;
88 84
89 // Last congestion window in packets computed by cubic function. 85 // Last congestion window in packets computed by cubic function.
90 QuicTcpCongestionWindow last_target_congestion_window_; 86 QuicPacketCount last_target_congestion_window_;
91 87
92 // QuicConnectionStats includes congestion control related stats. 88 // QuicConnectionStats includes congestion control related stats.
93 QuicConnectionStats* stats_; 89 QuicConnectionStats* stats_;
94 90
95 DISALLOW_COPY_AND_ASSIGN(Cubic); 91 DISALLOW_COPY_AND_ASSIGN(Cubic);
96 }; 92 };
97 93
98 } // namespace net 94 } // namespace net
99 95
100 #endif // NET_QUIC_CONGESTION_CONTROL_CUBIC_H_ 96 #endif // NET_QUIC_CONGESTION_CONTROL_CUBIC_H_
OLDNEW
« no previous file with comments | « net/proxy/proxy_info_unittest.cc ('k') | net/quic/congestion_control/cubic.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698