Examples with LockID org.apache.accumulo.fate.zookeeper.ZooUtil.LockID used on opensource projects

Example 1 with LockID

use of org.apache.accumulo.fate.zookeeper.ZooUtil.LockID in project accumulo by apache.

the class ConditionalWriterImpl method invalidateSession.

/**
 * The purpose of this code is to ensure that a conditional mutation will not execute when its status is unknown. This allows a user to read the row when the
 * status is unknown and not have to worry about the tserver applying the mutation after the scan.
 *
 * <p>
 * If a conditional mutation is taking a long time to process, then this method will wait for it to finish... unless this exceeds timeout.
 */
private void invalidateSession(SessionID sessionId, HostAndPort location) throws AccumuloException, AccumuloSecurityException, TableNotFoundException {
    long sleepTime = 50;
    long startTime = System.currentTimeMillis();
    Instance instance = context.getInstance();
    LockID lid = new LockID(ZooUtil.getRoot(instance) + Constants.ZTSERVERS, sessionId.lockId);
    ZooCacheFactory zcf = new ZooCacheFactory();
    while (true) {
        if (!ZooLock.isLockHeld(zcf.getZooCache(instance.getZooKeepers(), instance.getZooKeepersSessionTimeOut()), lid)) {
            // ACCUMULO-1152 added a tserver lock check to the tablet location cache, so this invalidation prevents future attempts to contact the
            // tserver even its gone zombie and is still running w/o a lock
            locator.invalidateCache(context.getInstance(), location.toString());
            return;
        }
        try {
            // if the mutation is currently processing, this method will block until its done or times out
            invalidateSession(sessionId.sessionID, location);
            return;
        } catch (TApplicationException tae) {
            throw new AccumuloServerException(location.toString(), tae);
        } catch (TException e) {
            locator.invalidateCache(context.getInstance(), location.toString());
        }
        if ((System.currentTimeMillis() - startTime) + sleepTime > timeout)
            throw new TimedOutException(Collections.singleton(location.toString()));
        sleepUninterruptibly(sleepTime, TimeUnit.MILLISECONDS);
        sleepTime = Math.min(2 * sleepTime, MAX_SLEEP);
    }
}