Increase size of the the adb packets sent over the wire
The reason behing this change is to increase the adb push/pull speed
with reduceing the number of packets sent between the host and the
device because the communication is heavily bound by packet latency.
The change maintains two way compatibility in the communication
protocol with negotiating a packet size between the target and the
host with the CONNECT packets.
After this change the push/pull speeds improved significantly
(measured from Linux-x86_64 with 100MB of data):
| Old push | Old pull || New push | New pull |
-----------------------------------------------------------
Hammerhead | 4.6 MB/s | 3.9 MB/s || 13.1 MB/s | 16.5 MB/s |
-----------------------------------------------------------
Volantis | 6.0 MB/s | 6.2 MS/s || 25.9 MB/s | 29.0 MB/s |
-----------------------------------------------------------
Fugu | 6.0 MB/s | 5.1 MB/s || 27.9 MB/s | 33.2 MB/s |
-----------------------------------------------------------
Change-Id: Id9625de31266e43394289e325c7e7e473379c5d8
diff --git a/adb/adb.h b/adb/adb.h
index 31fe3a5..357be51 100644
--- a/adb/adb.h
+++ b/adb/adb.h
@@ -25,7 +25,9 @@
#include "adb_trace.h"
#include "fdevent.h"
-#define MAX_PAYLOAD 4096
+constexpr size_t MAX_PAYLOAD_V1 = 4 * 1024;
+constexpr size_t MAX_PAYLOAD_V2 = 256 * 1024;
+constexpr size_t MAX_PAYLOAD = MAX_PAYLOAD_V2;
#define A_SYNC 0x434e5953
#define A_CNXN 0x4e584e43
@@ -137,6 +139,8 @@
/* A socket is bound to atransport */
atransport *transport;
+
+ size_t get_max_payload() const;
};
@@ -193,6 +197,8 @@
atransport() {
auth_fde = {};
transport_fde = {};
+ protocol_version = A_VERSION;
+ max_payload = MAX_PAYLOAD;
}
virtual ~atransport() {}
@@ -234,7 +240,14 @@
const char* connection_state_name() const;
+ void update_version(int version, size_t payload);
+ int get_protocol_version() const;
+ size_t get_max_payload() const;
+
private:
+ int protocol_version;
+ size_t max_payload;
+
DISALLOW_COPY_AND_ASSIGN(atransport);
};