public void UpdateBlock(BlockInfo block)
{
if (block != null)
{
try
{
Trace.TraceInformation("Received update for block {0}", block);
AzureBlockStore.Instance.ReceiveBlock(block);
}
catch (Exception ex)
{
Trace.TraceError("Error receiving block {0}. Cause: {1}", block, ex);
// TODO: Should we drop some/all cached blocks for the same store to force a re-read from blobstore?
/*
AzureBlockStore.Instance.DropBlock(block.StoreName, block.Offset);
if (block.Offset > AzureBlockStore.Instance.BlockSize)
{
AzureBlockStore.Instance.DropBlock(block.StoreName,
block.Offset - AzureBlockStore.Instance.BlockSize);
}
*/
// Rethrow the exception as a service fault so that the sender knows this receiver has a problem.
throw;
}
}
}
public void Insert(BlockInfo block)
{
block.LastAccess = DateTime.UtcNow.Ticks;
_cache[MakeKey(block)] = block;
//Trace.WriteLine(String.Format("BlockStoreCache: Insert {0} with key {1}", block, MakeKey(block)));
if (_cache.Count > _maxBlockCount && !_evictionStarted)
{
Task.Factory.StartNew(EvictOldBlocks);
}
if (block.Length == AzureBlockStore.AzureBlockSize)
{
WriteToDiskCache(block);
}
}
private static string MakeKey(BlockInfo block)
{
return MakeKey(block.StoreName, block.Offset);
}
private void WriteToDiskCache(BlockInfo block)
{
// Start a background thread to write the block to the disk
Task.Factory.StartNew(
() =>
{
try
{
_diskCache.PutData(MakeKey(block), block.Data);
}
catch (Exception e)
{
Trace.TraceWarning("Error writing block to disk cache: {0}", e);
}
});
}
private static string MakeCacheFileName(BlockInfo block)
{
return MakeCacheFileName(MakeKey(block));
}