/**
* Upgrade to any release after 0.22 (0.22 included) release e.g. 0.22 => 0.23 Upgrade procedure
* is as follows:
*
* <ol>
* <li>If <SD>/current/<bpid>/previous exists then delete it
* <li>Rename <SD>/current/<bpid>/current to <SD>/current/bpid/current/previous.tmp
* <li>Create new <SD>current/<bpid>/current directory
* <ol>
* <li>Hard links for block files are created from previous.tmp to current
* <li>Save new version file in current directory
* </ol>
* <li>Rename previous.tmp to previous
* </ol>
*
* @param bpSd storage directory <SD>/current/<bpid>
* @param nsInfo Namespace Info from the namenode
* @throws IOException on error
*/
void doUpgrade(DataNode datanode, StorageDirectory bpSd, NamespaceInfo nsInfo)
throws IOException {
// Upgrading is applicable only to release with federation or after
if (!DataNodeLayoutVersion.supports(LayoutVersion.Feature.FEDERATION, layoutVersion)) {
return;
}
LOG.info(
"Upgrading block pool storage directory "
+ bpSd.getRoot()
+ ".\n old LV = "
+ this.getLayoutVersion()
+ "; old CTime = "
+ this.getCTime()
+ ".\n new LV = "
+ HdfsConstants.DATANODE_LAYOUT_VERSION
+ "; new CTime = "
+ nsInfo.getCTime());
// get <SD>/previous directory
String dnRoot = getDataNodeStorageRoot(bpSd.getRoot().getCanonicalPath());
StorageDirectory dnSdStorage = new StorageDirectory(new File(dnRoot));
File dnPrevDir = dnSdStorage.getPreviousDir();
// If <SD>/previous directory exists delete it
if (dnPrevDir.exists()) {
deleteDir(dnPrevDir);
}
File bpCurDir = bpSd.getCurrentDir();
File bpPrevDir = bpSd.getPreviousDir();
assert bpCurDir.exists() : "BP level current directory must exist.";
cleanupDetachDir(new File(bpCurDir, DataStorage.STORAGE_DIR_DETACHED));
// 1. Delete <SD>/current/<bpid>/previous dir before upgrading
if (bpPrevDir.exists()) {
deleteDir(bpPrevDir);
}
File bpTmpDir = bpSd.getPreviousTmp();
assert !bpTmpDir.exists() : "previous.tmp directory must not exist.";
// 2. Rename <SD>/current/<bpid>/current to
// <SD>/current/<bpid>/previous.tmp
rename(bpCurDir, bpTmpDir);
// 3. Create new <SD>/current with block files hardlinks and VERSION
linkAllBlocks(datanode, bpTmpDir, bpCurDir);
this.layoutVersion = HdfsConstants.DATANODE_LAYOUT_VERSION;
assert this.namespaceID == nsInfo.getNamespaceID()
: "Data-node and name-node layout versions must be the same.";
this.cTime = nsInfo.getCTime();
writeProperties(bpSd);
// 4.rename <SD>/current/<bpid>/previous.tmp to
// <SD>/current/<bpid>/previous
rename(bpTmpDir, bpPrevDir);
LOG.info("Upgrade of block pool " + blockpoolID + " at " + bpSd.getRoot() + " is complete");
}
