TrafficStats: fix uncertainty in flushing network traffic
Flushing TCP traffic isn't reliable enough to force a packet on the socket,
even with Nagle disabled.
The kernel's socket sendto() is being invoked with 1024 bytes each time,
but something deeper in the stack is merging packets.
So now we wait 5ms between each of the 1024 packets after flushing.
This allows running the test overnight in a loop without failure
instead of only ~5 times.
The error messages are now more detailed.
Bug: 10668088
Change-Id: Ic47bec81c6dba2fad8b96eb4a41f183115c371de
diff --git a/tests/cts/net/src/android/net/cts/TrafficStatsTest.java b/tests/cts/net/src/android/net/cts/TrafficStatsTest.java
index 180d259..9483bdc 100644
--- a/tests/cts/net/src/android/net/cts/TrafficStatsTest.java
+++ b/tests/cts/net/src/android/net/cts/TrafficStatsTest.java
@@ -19,7 +19,11 @@
import android.net.TrafficStats;
import android.os.Process;
import android.test.AndroidTestCase;
+import android.util.Log;
+import java.io.BufferedReader;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
@@ -29,6 +33,8 @@
import java.util.concurrent.TimeUnit;
public class TrafficStatsTest extends AndroidTestCase {
+ private static final String LOG_TAG = "TrafficStatsTest";
+
public void testValidMobileStats() {
// We can't assume a mobile network is even present in this test, so
// we simply assert that a valid value is returned.
@@ -75,19 +81,39 @@
return packetCount * (20 + 32 + bytes);
}
+ private void accessOwnTrafficStats() throws IOException {
+ final int ownAppUid = getContext().getApplicationInfo().uid;
+ Log.d(LOG_TAG, "accesOwnTrafficStatsWithTags(): about to read qtaguid stats for own uid " + ownAppUid);
+
+ boolean foundOwnDetailedStats = false;
+ try {
+ BufferedReader qtaguidReader = new BufferedReader(new FileReader("/proc/net/xt_qtaguid/stats"));
+ String line;
+ while ((line = qtaguidReader.readLine()) != null) {
+ String tokens[] = line.split(" ");
+ if (tokens.length > 3 && tokens[3].equals(String.valueOf(ownAppUid))) {
+ Log.d(LOG_TAG, "accessOwnTrafficStatsWithTags(): got own stats: " + line);
+ }
+ }
+ qtaguidReader.close();
+ } catch (FileNotFoundException e) {
+ fail("Was not able to access qtaguid/stats: " + e);
+ }
+ }
+
public void testTrafficStatsForLocalhost() throws IOException {
- long mobileTxPacketsBefore = TrafficStats.getMobileTxPackets();
- long mobileRxPacketsBefore = TrafficStats.getMobileRxPackets();
- long mobileTxBytesBefore = TrafficStats.getMobileTxBytes();
- long mobileRxBytesBefore = TrafficStats.getMobileRxBytes();
- long totalTxPacketsBefore = TrafficStats.getTotalTxPackets();
- long totalRxPacketsBefore = TrafficStats.getTotalRxPackets();
- long totalTxBytesBefore = TrafficStats.getTotalTxBytes();
- long totalRxBytesBefore = TrafficStats.getTotalRxBytes();
- long uidTxBytesBefore = TrafficStats.getUidTxBytes(Process.myUid());
- long uidRxBytesBefore = TrafficStats.getUidRxBytes(Process.myUid());
- long uidTxPacketsBefore = TrafficStats.getUidTxPackets(Process.myUid());
- long uidRxPacketsBefore = TrafficStats.getUidRxPackets(Process.myUid());
+ final long mobileTxPacketsBefore = TrafficStats.getMobileTxPackets();
+ final long mobileRxPacketsBefore = TrafficStats.getMobileRxPackets();
+ final long mobileTxBytesBefore = TrafficStats.getMobileTxBytes();
+ final long mobileRxBytesBefore = TrafficStats.getMobileRxBytes();
+ final long totalTxPacketsBefore = TrafficStats.getTotalTxPackets();
+ final long totalRxPacketsBefore = TrafficStats.getTotalRxPackets();
+ final long totalTxBytesBefore = TrafficStats.getTotalTxBytes();
+ final long totalRxBytesBefore = TrafficStats.getTotalRxBytes();
+ final long uidTxBytesBefore = TrafficStats.getUidTxBytes(Process.myUid());
+ final long uidRxBytesBefore = TrafficStats.getUidRxBytes(Process.myUid());
+ final long uidTxPacketsBefore = TrafficStats.getUidTxPackets(Process.myUid());
+ final long uidRxPacketsBefore = TrafficStats.getUidRxPackets(Process.myUid());
// Transfer 1MB of data across an explicitly localhost socket.
final int byteCount = 1024;
@@ -104,22 +130,36 @@
socket.setTcpNoDelay(true);
OutputStream out = socket.getOutputStream();
byte[] buf = new byte[byteCount];
+ TrafficStats.setThreadStatsTag(0x42);
+ TrafficStats.tagSocket(socket);
+ accessOwnTrafficStats();
for (int i = 0; i < packetCount; i++) {
out.write(buf);
out.flush();
+ try {
+ // Bug: 10668088, Even with Nagle disabled, and flushing the 1024 bytes
+ // the kernel still regroups data into a larger packet.
+ Thread.sleep(5);
+ } catch (InterruptedException e) {
+ }
}
out.close();
socket.close();
+ accessOwnTrafficStats();
} catch (IOException e) {
+ Log.i(LOG_TAG, "Badness during writes to socket: " + e);
}
}
}.start();
+ int read = 0;
try {
Socket socket = server.accept();
+ socket.setTcpNoDelay(true);
+ TrafficStats.setThreadStatsTag(0x43);
+ TrafficStats.tagSocket(socket);
InputStream in = socket.getInputStream();
byte[] buf = new byte[byteCount];
- int read = 0;
while (read < byteCount * packetCount) {
int n = in.read(buf);
assertTrue("Unexpected EOF", n > 0);
@@ -128,6 +168,7 @@
} finally {
server.close();
}
+ assertTrue("Not all data read back", read >= byteCount * packetCount);
// It's too fast to call getUidTxBytes function.
try {
@@ -163,18 +204,30 @@
* + 7 approx.: syn, syn-ack, ack, fin-ack, ack, fin-ack, ack;
* but sometimes the last find-acks just vanish, so we set a lower limit of +5.
*/
- assertTrue("uidtxp: " + uidTxPacketsBefore + " -> " + uidTxPacketsAfter + " delta=" + uidTxDeltaPackets,
- uidTxDeltaPackets >= packetCount + 5 &&
- uidTxDeltaPackets <= packetCount + packetCount + 7);
- assertTrue("uidrxp: " + uidRxPacketsBefore + " -> " + uidRxPacketsAfter + " delta=" + uidRxDeltaPackets,
- uidRxDeltaPackets >= packetCount + 5 &&
- uidRxDeltaPackets <= packetCount + packetCount + 7);
- assertTrue("uidtxb: " + uidTxBytesBefore + " -> " + uidTxBytesAfter + " delta=" + uidTxDeltaBytes,
- uidTxDeltaBytes >= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(5, 0) &&
- uidTxDeltaBytes <= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(packetCount + 7, 0));
- assertTrue("uidrxb: " + uidRxBytesBefore + " -> " + uidRxBytesAfter + " delta=" + uidRxDeltaBytes,
- uidRxDeltaBytes >= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(5, 0) &&
- uidRxDeltaBytes <= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(packetCount + 7, 0));
+ final int maxExpectedExtraPackets = 7;
+ final int minExpectedExtraPackets = 5;
+
+
+ assertTrue("uidtxp: " + uidTxPacketsBefore + " -> " + uidTxPacketsAfter + " delta=" + uidTxDeltaPackets +
+ " Wanted: " + uidTxDeltaPackets + ">=" + packetCount + "+" + minExpectedExtraPackets + " && " +
+ uidTxDeltaPackets + "<=" + packetCount + "+" + packetCount + "+" + maxExpectedExtraPackets,
+ uidTxDeltaPackets >= packetCount + minExpectedExtraPackets &&
+ uidTxDeltaPackets <= packetCount + packetCount + maxExpectedExtraPackets);
+ assertTrue("uidrxp: " + uidRxPacketsBefore + " -> " + uidRxPacketsAfter + " delta=" + uidRxDeltaPackets +
+ " Wanted: " + uidRxDeltaPackets + ">=" + packetCount + "+" + minExpectedExtraPackets + " && " +
+ uidRxDeltaPackets + "<=" + packetCount + "+" + packetCount + "+" + maxExpectedExtraPackets,
+ uidRxDeltaPackets >= packetCount + minExpectedExtraPackets &&
+ uidRxDeltaPackets <= packetCount + packetCount + maxExpectedExtraPackets);
+ assertTrue("uidtxb: " + uidTxBytesBefore + " -> " + uidTxBytesAfter + " delta=" + uidTxDeltaBytes +
+ " Wanted: " + uidTxDeltaBytes + ">=" + tcpPacketToIpBytes(packetCount, byteCount) + "+" + tcpPacketToIpBytes(minExpectedExtraPackets, 0) + " && " +
+ uidTxDeltaBytes + "<=" + tcpPacketToIpBytes(packetCount, byteCount) + "+" + tcpPacketToIpBytes(packetCount + maxExpectedExtraPackets, 0),
+ uidTxDeltaBytes >= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(minExpectedExtraPackets, 0) &&
+ uidTxDeltaBytes <= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(packetCount + maxExpectedExtraPackets, 0));
+ assertTrue("uidrxb: " + uidRxBytesBefore + " -> " + uidRxBytesAfter + " delta=" + uidRxDeltaBytes +
+ " Wanted: " + uidRxDeltaBytes + ">=" + tcpPacketToIpBytes(packetCount, byteCount) + "+" + tcpPacketToIpBytes(minExpectedExtraPackets, 0) + " && " +
+ uidRxDeltaBytes + "<=" + tcpPacketToIpBytes(packetCount, byteCount) + "+" + tcpPacketToIpBytes(packetCount + maxExpectedExtraPackets, 0),
+ uidRxDeltaBytes >= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(minExpectedExtraPackets, 0) &&
+ uidRxDeltaBytes <= tcpPacketToIpBytes(packetCount, byteCount) + tcpPacketToIpBytes(packetCount + maxExpectedExtraPackets, 0));
// Localhost traffic *does* count against total stats.
// Fudge by 132 packets of 1500 bytes not related to the test.