/**
* Removed rejected merge requests from merge_rsps and coords. This method has a lock on
* merge_rsps
*/
private void removeRejectedMergeRequests(Collection<Address> coords) {
for (Map.Entry<Address, MergeData> entry : merge_rsps.getResults().entrySet()) {
Address member = entry.getKey();
MergeData data = entry.getValue();
if (data.merge_rejected) {
if (data.getSender() != null) coords.remove(data.getSender());
merge_rsps.remove(member);
}
}
}
/**
* Merge all digests into one. For each sender, the new value is max(highest_delivered),
* max(highest_received). This method has a lock on merge_rsps
*/
private Digest consolidateDigests(List<MergeData> merge_rsps, int num_mbrs) {
MutableDigest retval = new MutableDigest(num_mbrs);
for (MergeData data : merge_rsps) {
Digest tmp_digest = data.getDigest();
if (tmp_digest == null) continue;
retval.merge(tmp_digest);
}
return retval.copy();
}
/**
* Merge all digests into one. For each sender, the new value is min(low_seqno),
* max(high_seqno), max(high_seqno_seen). This method has a lock on merge_rsps
*/
private Digest consolidateDigests(Vector<MergeData> merge_rsps, int num_mbrs) {
MutableDigest retval = new MutableDigest(num_mbrs);
for (MergeData data : merge_rsps) {
Digest tmp_digest = data.getDigest();
if (tmp_digest == null) {
if (log.isErrorEnabled()) log.error("tmp_digest == null; skipping");
continue;
}
retval.merge(tmp_digest);
}
return retval.copy();
}
/**
* Merge all MergeData. All MergeData elements should be disjunct (both views and digests).
* However, this method is prepared to resolve duplicate entries (for the same member).
* Resolution strategy for views is to merge only 1 of the duplicate members. Resolution
* strategy for digests is to take the higher seqnos for duplicate digests.
*
* <p>After merging all members into a Membership and subsequent sorting, the first member of
* the sorted membership will be the new coordinator. This method has a lock on merge_rsps.
*
* @param merge_rsps A list of MergeData items. Elements with merge_rejected=true were removed
* before. Is guaranteed not to be null and to contain at least 1 member.
*/
private MergeData consolidateMergeData(Vector<MergeData> merge_rsps) {
long logical_time = 0; // for new_vid
Membership new_mbrs = new Membership();
Vector<View> subgroups =
new Vector<View>(11); // contains a list of Views, each View is a subgroup
for (MergeData tmp_data : merge_rsps) {
View tmp_view = tmp_data.getView();
if (tmp_view != null) {
ViewId tmp_vid = tmp_view.getVid();
if (tmp_vid != null) {
// compute the new view id (max of all vids +1)
logical_time = Math.max(logical_time, tmp_vid.getId());
}
// merge all membership lists into one (prevent duplicates)
new_mbrs.add(tmp_view.getMembers());
subgroups.addElement((View) tmp_view.clone());
}
}
// the new coordinator is the first member of the consolidated & sorted membership list
new_mbrs.sort();
Address new_coord = new_mbrs.size() > 0 ? new_mbrs.elementAt(0) : null;
if (new_coord == null) {
if (log.isErrorEnabled()) log.error("new_coord == null");
return null;
}
// should be the highest view ID seen up to now plus 1
ViewId new_vid = new ViewId(new_coord, logical_time + 1);
// determine the new view
MergeView new_view = new MergeView(new_vid, new_mbrs.getMembers(), subgroups);
// determine the new digest
Digest new_digest = consolidateDigests(merge_rsps, new_mbrs.size());
if (new_digest == null) {
if (log.isErrorEnabled())
log.error("Merge leader " + gms.local_addr + ": could not consolidate digest for merge");
return null;
}
if (log.isDebugEnabled())
log.debug(
"Merge leader "
+ gms.local_addr
+ ": consolidated view="
+ new_view
+ "\nconsolidated digest="
+ new_digest);
return new MergeData(gms.local_addr, new_view, new_digest);
}
/**
* Merge all MergeData. All MergeData elements should be disjunct (both views and digests).
* However, this method is prepared to resolve duplicate entries (for the same member).
* Resolution strategy for views is to merge only 1 of the duplicate members. Resolution
* strategy for digests is to take the higher seqnos for duplicate digests.
*
* <p>After merging all members into a Membership and subsequent sorting, the first member of
* the sorted membership will be the new coordinator. This method has a lock on merge_rsps.
*
* @param merge_rsps A list of MergeData items. Elements with merge_rejected=true were removed
* before. Is guaranteed not to be null and to contain at least 1 member.
*/
private MergeData consolidateMergeData(List<MergeData> merge_rsps) {
long logical_time = 0; // for new_vid
List<View> subgroups =
new ArrayList<View>(11); // contains a list of Views, each View is a subgroup
Collection<Collection<Address>> sub_mbrships = new ArrayList<Collection<Address>>();
for (MergeData tmp_data : merge_rsps) {
View tmp_view = tmp_data.getView();
if (tmp_view != null) {
ViewId tmp_vid = tmp_view.getVid();
if (tmp_vid != null) {
// compute the new view id (max of all vids +1)
logical_time = Math.max(logical_time, tmp_vid.getId());
}
// merge all membership lists into one (prevent duplicates)
sub_mbrships.add(new ArrayList<Address>(tmp_view.getMembers()));
subgroups.add(tmp_view.copy());
}
}
// determine the new digest
Digest new_digest = consolidateDigests(merge_rsps, merge_rsps.size());
if (new_digest == null) return null;
// remove all members from the new member list that are not in the digest
Collection<Address> digest_mbrs = new_digest.getMembers();
for (Collection<Address> coll : sub_mbrships) coll.retainAll(digest_mbrs);
List<Address> merged_mbrs = gms.computeNewMembership(sub_mbrships);
// the new coordinator is the first member of the consolidated & sorted membership list
Address new_coord = merged_mbrs.isEmpty() ? null : merged_mbrs.get(0);
if (new_coord == null) return null;
// should be the highest view ID seen up to now plus 1
ViewId new_vid = new ViewId(new_coord, logical_time + 1);
// determine the new view
MergeView new_view = new MergeView(new_vid, merged_mbrs, subgroups);
if (log.isTraceEnabled())
log.trace(
gms.local_addr
+ ": consolidated view="
+ new_view
+ "\nconsolidated digest="
+ new_digest);
return new MergeData(gms.local_addr, new_view, new_digest);
}
/**
* If merge_id is not equal to this.merge_id then discard. Else cast the view/digest to all
* members of this group.
*/
public void handleMergeView(final MergeData data, final MergeId merge_id) {
if (!matchMergeId(merge_id)) {
if (log.isErrorEnabled())
log.error("merge_ids don't match (or are null); merge view discarded");
return;
}
// only send to our *current* members, if we have A and B being merged (we are B), then we would
// *not*
// receive a VIEW_ACK from A because A doesn't see us in the pre-merge view yet and discards the
// view
// [JGRP-700] - FLUSH: flushing should span merge
// we have to send new view only to current members and we should not wait
// for view acks from newly merged mebers
List<Address> newViewMembers = new Vector<Address>(data.view.getMembers());
newViewMembers.removeAll(gms.members.getMembers());
gms.castViewChangeWithDest(data.view, data.digest, null, newViewMembers);
// if we have flush in stack send ack back to merge coordinator
if (gms.flushProtocolInStack) {
Message ack = new Message(data.getSender(), null, null);
ack.setFlag(Message.OOB);
GMS.GmsHeader ack_hdr = new GMS.GmsHeader(GMS.GmsHeader.INSTALL_MERGE_VIEW_OK);
ack.putHeader(gms.getId(), ack_hdr);
gms.getDownProtocol().down(new Event(Event.MSG, ack));
}
cancelMerge(merge_id);
}
public void handleMergeResponse(MergeData data, MergeId merge_id) {
if (!matchMergeId(merge_id)) {
if (log.isTraceEnabled())
log.trace(
gms.local_addr
+ ": this.merge_id ("
+ this.merge_id
+ ") is different from merge_id "
+ merge_id
+ " sent by "
+ data.getSender()
+ " as merge response, discarding it");
return;
}
merge_rsps.add(data.getSender(), data);
}
/**
* Removed rejected merge requests from merge_rsps and coords. This method has a lock on
* merge_rsps
*/
private void removeRejectedMergeRequests(Collection<Address> coords) {
int num_removed = 0;
for (Iterator<Map.Entry<Address, MergeData>> it =
merge_rsps.getResults().entrySet().iterator();
it.hasNext(); ) {
Map.Entry<Address, MergeData> entry = it.next();
MergeData data = entry.getValue();
if (data.merge_rejected) {
if (data.getSender() != null) coords.remove(data.getSender());
it.remove();
num_removed++;
}
}
if (num_removed > 0) {
if (log.isTraceEnabled())
log.trace(gms.local_addr + ": removed " + num_removed + " rejected merge responses");
}
}
public void handleMergeResponse(MergeData data, MergeId merge_id) {
if (!matchMergeId(merge_id)) {
if (log.isErrorEnabled())
log.error(
gms.local_addr
+ ": this.merge_id ("
+ this.merge_id
+ ") is different from merge_id ("
+ merge_id
+ ')');
return;
}
merge_rsps.add(data.getSender(), data);
}
/**
* If merge_id is not equal to this.merge_id then discard. Else cast the view/digest to all
* members of this group.
*/
public void handleMergeView(final MergeData data, final MergeId merge_id) {
if (!matchMergeId(merge_id)) {
if (log.isTraceEnabled())
log.trace(
gms.local_addr
+ ": merge_ids (mine: "
+ this.merge_id
+ ", received: "
+ merge_id
+ ") don't match; merge view "
+ data.view.getViewId()
+ " is discarded");
return;
}
// only send to our *current* members, if we have A and B being merged (we are B), then we would
// *not*
// want to block on a VIEW_ACK from A because A doesn't see us in the pre-merge view yet and
// discards the view
List<Address> newViewMembers = new ArrayList<Address>(data.view.getMembers());
newViewMembers.removeAll(gms.members.getMembers());
try {
gms.castViewChange(data.view, data.digest, null, newViewMembers);
// if we have flush in stack send ack back to merge coordinator
if (gms.flushProtocolInStack) { // [JGRP-700] - FLUSH: flushing should span merge
Message ack =
new Message(data.getSender()).setFlag(Message.Flag.OOB, Message.Flag.INTERNAL);
GMS.GmsHeader ack_hdr = new GMS.GmsHeader(GMS.GmsHeader.INSTALL_MERGE_VIEW_OK);
ack.putHeader(gms.getId(), ack_hdr);
gms.getDownProtocol().down(new Event(Event.MSG, ack));
}
} finally {
cancelMerge(merge_id);
}
}