// Alternates between turning network writes on and off in a loop.
// Runs in a background goroutine and is started once at the very beginning of a test.
func (ts *syncTestSystem) runNetwork() {
t := ts.t
// Network initially on
t.Log("Setting global write drop percent to 0%")
lspnet.SetWriteDropPercent(0)
for {
select {
case <-ts.exitChan:
t.Log("Received exit signal in runNetwork. Shutting down...")
return
default:
t.Log("Waiting for master...")
<-ts.masterToNetworkChan
t.Log("Setting global write drop percent to 100%")
lspnet.SetWriteDropPercent(100)
ts.networkToMasterChan <- struct{}{}
t.Log("Waiting for master...")
<-ts.masterToNetworkChan
t.Log("Setting global write drop percent to 0%")
lspnet.SetWriteDropPercent(0)
ts.networkToMasterChan <- struct{}{}
t.Logf("Sleeping for %d ms", 2*ts.params.EpochMillis)
time.Sleep(time.Duration(2*ts.params.EpochMillis) * time.Millisecond)
}
}
}
func (ts *testSystem) runTest(timeout int) {
lspnet.SetWriteDropPercent(ts.dropPercent)
defer lspnet.ResetDropPercent()
fmt.Printf("=== %s (%d clients, %d msgs/client, %d%% drop rate, %d window size)\n",
ts.desc, ts.numClients, ts.numMsgs, ts.dropPercent, ts.params.WindowSize)
clientDoneChan := make(chan bool, ts.numClients)
go ts.runServer()
for i := range ts.clients {
go ts.runClient(i, clientDoneChan)
}
timeoutChan := time.After(time.Duration(timeout) * time.Millisecond)
for _ = range ts.clients {
select {
case <-timeoutChan:
close(ts.exitChan)
ts.t.Fatalf("Test timed out after %.2f secs", float64(timeout)/1000.0)
case ok := <-clientDoneChan:
if !ok {
// May or may not close the server goroutine. There's no guarantee
// since we do not explicitly test the students' Close implementations
// in these basic tests.
close(ts.exitChan)
ts.t.Fatal("Client failed due to an error.")
}
}
}
close(ts.exitChan)
}