tsnet: send less data in metrics integration test

this commit reduced the amount of data sent in the metrics
data integration test from 10MB to 1MB.

On various machines 10MB was quite flaky, while 1MB has not failed
once on 10000 runs.

Updates tailscale#13420

Signed-off-by: Kristoffer Dalby <[email protected]>

Author: kradalby

tsnet/tsnet_test.go

@@ -1015,8 +1015,8 @@ func TestUserMetrics(t *testing.T) {
 
 	mustDirect(t, t.Logf, lc1, lc2)
 
-	// 10 megabytes
-	bytesToSend := 10 * 1024 * 1024
+	// 1 megabytes
+	bytesToSend := 1 * 1024 * 1024
 
 	// This asserts generates some traffic, it is factored out
 	// of TestUDPConn.
@@ -1059,14 +1059,13 @@ func TestUserMetrics(t *testing.T) {
 		t.Errorf("metrics1, tailscaled_approved_routes: got %v, want %v", got, want)
 	}
 
-	// Verify that the amount of data recorded in bytes is higher or equal to the
-	// 10 megabytes sent.
+	// Verify that the amount of data recorded in bytes is higher or equal to the data sent
 	inboundBytes1 := parsedMetrics1[`tailscaled_inbound_bytes_total{path="direct_ipv4"}`]
 	if inboundBytes1 < float64(bytesToSend) {
 		t.Errorf(`metrics1, tailscaled_inbound_bytes_total{path="direct_ipv4"}: expected higher (or equal) than %d, got: %f`, bytesToSend, inboundBytes1)
 	}
 
-	// But ensure that it is not too much higher than the 10 megabytes sent.
+	// But ensure that it is not too much higher than the data sent.
 	if inboundBytes1 > float64(bytesToSend)*bytesSentTolerance {
 		t.Errorf(`metrics1, tailscaled_inbound_bytes_total{path="direct_ipv4"}: expected lower than %f, got: %f`, float64(bytesToSend)*bytesSentTolerance, inboundBytes1)
 	}
@@ -1093,14 +1092,13 @@ func TestUserMetrics(t *testing.T) {
 		t.Errorf("metrics2, tailscaled_approved_routes: got %v, want %v", got, want)
 	}
 
-	// Verify that the amount of data recorded in bytes is higher or equal than the
-	// 10 megabytes sent.
+	// Verify that the amount of data recorded in bytes is higher or equal than the data sent.
 	outboundBytes2 := parsedMetrics2[`tailscaled_outbound_bytes_total{path="direct_ipv4"}`]
 	if outboundBytes2 < float64(bytesToSend) {
 		t.Errorf(`metrics2, tailscaled_outbound_bytes_total{path="direct_ipv4"}: expected higher (or equal) than %d, got: %f`, bytesToSend, outboundBytes2)
 	}
 
-	// But ensure that it is not too much higher than the 10 megabytes sent.
+	// But ensure that it is not too much higher than the data sent.
 	if outboundBytes2 > float64(bytesToSend)*bytesSentTolerance {
 		t.Errorf(`metrics2, tailscaled_outbound_bytes_total{path="direct_ipv4"}: expected lower than %f, got: %f`, float64(bytesToSend)*bytesSentTolerance, outboundBytes2)
 	}