/// <exception cref="System.IO.IOException"/>
internal static void DoMerge(CheckpointSignature sig, RemoteEditLogManifest manifest
, bool loadImage, FSImage dstImage, FSNamesystem dstNamesystem)
{
NNStorage dstStorage = dstImage.GetStorage();
dstStorage.SetStorageInfo(sig);
if (loadImage)
{
FilePath file = dstStorage.FindImageFile(NNStorage.NameNodeFile.Image, sig.mostRecentCheckpointTxId
);
if (file == null)
{
throw new IOException("Couldn't find image file at txid " + sig.mostRecentCheckpointTxId
+ " even though it should have " + "just been downloaded");
}
dstNamesystem.WriteLock();
try
{
dstImage.ReloadFromImageFile(file, dstNamesystem);
}
finally
{
dstNamesystem.WriteUnlock();
}
dstNamesystem.ImageLoadComplete();
}
// error simulation code for junit test
CheckpointFaultInjector.GetInstance().DuringMerge();
Checkpointer.RollForwardByApplyingLogs(manifest, dstImage, dstNamesystem);
// The following has the side effect of purging old fsimages/edit logs.
dstImage.SaveFSImageInAllDirs(dstNamesystem, dstImage.GetLastAppliedTxId());
dstStorage.WriteAll();
}