/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package com.bigdata.ha;
import java.io.IOException;
import java.rmi.Remote;
import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.Future;
import com.bigdata.ha.msg.IHAGatherReleaseTimeRequest;
import com.bigdata.ha.msg.IHANotifyReleaseTimeRequest;
import com.bigdata.ha.msg.IHANotifyReleaseTimeResponse;
import com.bigdata.journal.ITransactionService;
/**
* RMI interface for the {@link ITransactionService} for HA.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
*
* @see <a
* href="https://docs.google.com/document/d/14FO2yJFv_7uc5N0tvYboU-H6XbLEFpvu-G8RhAzvxrk/edit?pli=1#"
* > HA TXS Design Document </a>
*
* @see <a href="https://sourceforge.net/apps/trac/bigdata/ticket/623" > HA TXS
* / TXS Bottleneck </a>
*/
public interface HATXSGlue extends Remote {
/**
* Message used to request information about the earliest commit point that
* is pinned on a follower. This is used by the leader to make a decision
* about the new release time for the replication cluster.
* <p>
* Note: This message is used as part of a pattern where the leader
* instructs the followers to message the leader with their earliest commit
* point pinned by either a transaction or the minReleaseAge of their
* {@link ITransactionService} using
* {@link #notifyEarliestCommitTime(IHANotifyReleaseTimeResponse)}.
* <p>
* The message is a sync RMI call. The follower will clear an outcome and
* execute a task which runs asynchronously and messages back to the leader
* with its {@link IHANotifyReleaseTimeResponse}. The leader will report
* back the consensus release time. The outcome of these on the follower is
* not directly reported back to the leader, e.g., through a remote
* {@link Future} because this causes a DGC thread leak on the follower. See
* the ticket below. Instead, the follower notes the outcome of the gather
* operation and will vote "NO" in
* {@link HACommitGlue#prepare2Phase(IHA2PhasePrepareMessage)} unless it
* completes its side of the release time consensus protocol without error
* (that is, the otherwise unmonitored outcome of the asynchronous task for
* {@link #gatherMinimumVisibleCommitTime(IHAGatherReleaseTimeRequest)}).
*
* @param req
* The request from the leader.
*
* @see #notifyEarliestCommitTime(IHANotifyReleaseTimeResponse)
*
* @see <a href="https://sourceforge.net/apps/trac/bigdata/ticket/673" >
* Native thread leak in HAJournalServer process </a>
*/
void gatherMinimumVisibleCommitTime(IHAGatherReleaseTimeRequest req)
throws IOException;
/**
* Message used by the follower to notify the leader about the new release
* time that will be visible for new transaction starts. The leader then
* chooses the mimimum across itself and the followers.
*
* @param rsp
* The earliest pinned commit point on the follower.
*
* @return The earliest pinned commit point across the services joined with
* the met quorum.
*
* @throws BrokenBarrierException
* @throws InterruptedException
*/
IHANotifyReleaseTimeResponse notifyEarliestCommitTime(
IHANotifyReleaseTimeRequest req) throws IOException,
InterruptedException, BrokenBarrierException;
}