public void UpdateConfiguration(List <ReplicaInfo> replicaChain, int readViewHeadIndex, bool convertXStoreTableMode = false)
{
Parallel.ForEach(this.blobs, blob =>
{
ReplicatedTableConfigurationStore configurationStore = null;
long newViewId = 0;
if (!CloudBlobHelpers.TryReadBlob <ReplicatedTableConfigurationStore>(blob.Value, out configurationStore))
{
//This is the first time we are uploading the config
configurationStore = new ReplicatedTableConfigurationStore();
}
newViewId = configurationStore.ViewId + 1;
configurationStore.LeaseDuration = Constants.LeaseDurationInSec;
configurationStore.Timestamp = DateTime.UtcNow;
configurationStore.ReplicaChain = replicaChain;
configurationStore.ReadViewHeadIndex = readViewHeadIndex;
configurationStore.ConvertXStoreTableMode = convertXStoreTableMode;
configurationStore.ViewId = newViewId;
//If the read view head index is not 0, this means we are introducing 1 or more replicas at the head. For
//each such replica, update the view id in which it was added to the write view of the chain
if (readViewHeadIndex != 0)
{
for (int i = 0; i < readViewHeadIndex; i++)
{
replicaChain[i].ViewInWhichAddedToChain = newViewId;
}
}
try
{
//Step 1: Delete the current configuration
blob.Value.UploadText(Constants.ConfigurationStoreUpdatingText);
//Step 2: Wait for L + CF to make sure no pending transaction working on old views
// Chunzhi: removed this, original code hangs here
// Matt: restore this: it's essential for consistency.
Thread.Sleep(TimeSpan.FromSeconds(Constants.LeaseDurationInSec +
Constants.ClockFactorInSec));
//Step 3: Update new config
blob.Value.UploadText(JsonStore <ReplicatedTableConfigurationStore> .Serialize(configurationStore));
}
catch (StorageException e)
{
ReplicatedTableLogger.LogError("Updating the blob: {0} failed. Exception: {1}", blob.Value, e.Message);
}
});
//Invalidate the lastViewRefreshTime so that updated views get returned
this.lastViewRefreshTime = DateTime.MinValue;
}
/// <summary>
/// True, if the read and write views are the same. False, otherwise.
/// </summary>
public bool IsViewStable()
{
int viewStableCount = 0;
foreach (var blob in this.blobs)
{
ReplicatedTableConfigurationStore configurationStore;
if (!CloudBlobHelpers.TryReadBlob <ReplicatedTableConfigurationStore>(blob.Value, out configurationStore))
{
continue;
}
if (configurationStore.ReadViewHeadIndex == 0)
{
viewStableCount++;
}
}
return(viewStableCount >= this.quorumSize);
}
public void UpdateConfiguration(List <ReplicaInfo> replicaChain, int readViewHeadIndex, bool convertXStoreTableMode = false, long viewId = 0)
{
View currentView = GetWriteView();
if (viewId == 0)
{
if (!currentView.IsEmpty)
{
viewId = currentView.ViewId + 1;
}
else
{
viewId = 1;
}
}
ReplicatedTableConfigurationStore newConfig = new ReplicatedTableConfigurationStore
{
LeaseDuration = Constants.LeaseDurationInSec,
Timestamp = DateTime.UtcNow,
ReplicaChain = replicaChain,
ReadViewHeadIndex = readViewHeadIndex,
ConvertXStoreTableMode = convertXStoreTableMode,
ViewId = viewId
};
//If the read view head index is not 0, this means we are introducing 1 or more replicas at the head. For
//each such replica, update the view id in which it was added to the write view of the chain
if (readViewHeadIndex != 0)
{
for (int i = 0; i < readViewHeadIndex; i++)
{
replicaChain[i].ViewInWhichAddedToChain = viewId;
}
}
Parallel.ForEach(this.configManager.GetBlobs(), blob =>
{
ReplicatedTableConfigurationStore configurationStore = null;
string eTag;
/*
* TODO: (per Parveen Patel <*****@*****.**>)
* The below code is incomplete because we are supposed to use eTag to make the changes if the old blob exists.
* This is to support multiple clients updating the config, not a high priority scenario but something we should look at.
*/
ReplicatedTableReadBlobResult result = CloudBlobHelpers.TryReadBlob(
blob,
out configurationStore,
out eTag,
JsonStore <ReplicatedTableConfigurationStore> .Deserialize);
if (result.Code != ReadBlobCode.Success)
{
//This is the first time we are uploading the config
configurationStore = new ReplicatedTableConfigurationStore();
}
configurationStore = newConfig;
CloudBlobHelpers.TryWriteBlob(blob, configurationStore.ToJson());
});
this.configManager.Invalidate();
}
private void RefreshReadAndWriteViewsFromBlobs(object arg)
{
lock (this)
{
this.lastRenewedReadView = new View();
this.lastRenewedWriteView = new View();
DateTime refreshStartTime = DateTime.UtcNow;
Dictionary <long, List <CloudBlockBlob> > viewResult = new Dictionary <long, List <CloudBlockBlob> >();
foreach (var blob in this.blobs)
{
ReplicatedTableConfigurationStore configurationStore;
if (!CloudBlobHelpers.TryReadBlob <ReplicatedTableConfigurationStore>(blob.Value, out configurationStore))
{
continue;
}
if (configurationStore.ViewId <= 0)
{
ReplicatedTableLogger.LogInformational("ViewId={0} is invalid. Must be >= 1. Skipping this blob {1}.",
configurationStore.ViewId,
blob.Value.Uri);
continue;
}
List <CloudBlockBlob> viewBlobs;
if (!viewResult.TryGetValue(configurationStore.ViewId, out viewBlobs))
{
viewBlobs = new List <CloudBlockBlob>();
viewResult.Add(configurationStore.ViewId, viewBlobs);
}
viewBlobs.Add(blob.Value);
if (viewBlobs.Count >= this.quorumSize)
{
this.lastRenewedReadView.ViewId = this.lastRenewedWriteView.ViewId = configurationStore.ViewId;
for (int i = 0; i < configurationStore.ReplicaChain.Count; i++)
{
ReplicaInfo replica = configurationStore.ReplicaChain[i];
CloudTableClient tableClient = GetTableClientForReplica(replica);
if (replica != null && tableClient != null)
{
//Update the write view always
this.lastRenewedWriteView.Chain.Add(new Tuple <ReplicaInfo, CloudTableClient>(replica, tableClient));
//Update the read view only for replicas part of the view
if (i >= configurationStore.ReadViewHeadIndex)
{
this.lastRenewedReadView.Chain.Add(new Tuple <ReplicaInfo, CloudTableClient>(replica, tableClient));
}
//Note the time when the view was updated
this.lastViewRefreshTime = refreshStartTime;
this.ConvertXStoreTableMode = configurationStore.ConvertXStoreTableMode;
}
}
this.lastRenewedWriteView.ReadHeadIndex = configurationStore.ReadViewHeadIndex;
break;
}
}
}
}
