// https://issues.hibernatingrhinos.com/issue/RavenDB-12525
// The problem was when sync operates while there is no data to sync
// the sync operation continued with default properties
// and at the end, it updated the state with those properties
public void Sync_WhenThereIsNoJournalToSync_ShouldNotUpdateHeaderToDefault()
{
for (var i = 0; i < 100; i++)
{
using (var tx = Env.WriteTransaction())
{
var tree = tx.CreateTree("foo");
tree.Add("items/" + i, StreamFor("values/" + i));
tx.Commit();
}
}
Env.FlushLogToDataFile();
using (var operation = new SyncOperation(Env.Journal.Applicator))
{
operation.SyncDataFile();
}
using (var operation = new SyncOperation(Env.Journal.Applicator))
{
operation.SyncDataFile();
}
var journalInfo = Env.Journal.GetCurrentJournalInfo();
Assert.NotEqual(-1, journalInfo.LastSyncedJournal);
Assert.NotEqual(-1, journalInfo.LastSyncedTransactionId);
}
// As part of the sync operation, there are stages where the sync operation needs the flush lock
// and as part of the flush operation, there are stages the flush operation needs transaction write lock
// this can lead to a situation where the sync is waiting to flush waiting to write transaction
// so the sync pass his work that needs the flush lock to the flush operation if the lock is occupied
// and if the flush operation can do it while it waits to write transaction lock
//In this test, the sync is called while the flush is running and waiting to write transaction so the sync should not be blocked
public void CanSyncWhileFlushWaiteToWriteTransaction()
{
var syncMayFinishedEvent = new AutoResetEvent(false);
//Adding unsynced bytes so the sync thread will has work to do
for (var i = 0; i < 100; i++)
{
using (var tx = Env.WriteTransaction())
{
var tree = tx.CreateTree("foo");
tree.Add("items/" + i, StreamFor("values/" + i));
tx.Commit();
}
}
Env.FlushLogToDataFile();
//Adding unflushed bytes so the flush thread will has work to do
for (var i = 0; i < 100; i++)
{
using (var tx = Env.WriteTransaction())
{
var tree = tx.CreateTree("foo");
tree.Add("items/" + i, StreamFor("values/" + i));
tx.Commit();
}
}
var syncResult = false;
void Sync()
{
try
{
using (var operation = new SyncOperation(Env.Journal.Applicator))
{
syncResult = operation.SyncDataFile();
}
}
finally
{
syncMayFinishedEvent.Set();
}
}
void Flush()
{
try
{
using (Env.Journal.Applicator.TakeFlushingLock())
{
Task.Run((Action)Sync);
Env.FlushLogToDataFile();
}
}
catch (Exception)
{
syncMayFinishedEvent.Set();
}
}
// Write transaction lock is taken to block the flush
using (var tx = Env.WriteTransaction())
{
Task.Run((Action)Flush);
syncMayFinishedEvent.WaitOne(TimeSpan.FromSeconds(10));
Assert.True(syncResult);
var totalWrittenButUnsyncedBytes = Env.Journal.Applicator.TotalWrittenButUnsyncedBytes;
Assert.Equal(0, totalWrittenButUnsyncedBytes);
}
}
