Examples with Token org.apache.cassandra.dht.Token used on opensource projects

Example 46 with Token

use of org.apache.cassandra.dht.Token in project cassandra by apache.

the class ReplicationAwareTokenAllocator method evaluateImprovement.

/**
     * Evaluates the improvement in variance for both units and individual tokens when candidate is inserted into the
     * ring.
     */
private double evaluateImprovement(CandidateInfo<Unit> candidate, double optTokenOwnership, double newUnitMult) {
    double tokenChange = 0;
    UnitInfo<Unit> candidateUnit = candidate.owningUnit;
    Token candidateEnd = candidate.token;
    // Form a chain of units affected by the insertion to be able to qualify change of unit ownership.
    // A unit may be affected more than once.
    UnitAdjustmentTracker<Unit> unitTracker = new UnitAdjustmentTracker<>(candidateUnit);
    // Reflect change in ownership of the splitting token (candidate).
    tokenChange += applyOwnershipAdjustment(candidate, candidateUnit, candidate.replicationStart, candidateEnd, optTokenOwnership, unitTracker);
    // Loop through all vnodes that replicate candidate or split and update their ownership.
    ReplicationVisitor replicationVisitor = new ReplicationVisitor();
    for (TokenInfo<Unit> curr = candidate.split; !replicationVisitor.visitedAll(); curr = curr.next) {
        UnitInfo<Unit> currUnit = curr.owningUnit;
        if (!replicationVisitor.add(currUnit.group))
            // If this group is already seen, the token cannot be affected.
            continue;
        Token replicationEnd = curr.token;
        Token replicationStart = findUpdatedReplicationStart(curr, candidate);
        tokenChange += applyOwnershipAdjustment(curr, currUnit, replicationStart, replicationEnd, optTokenOwnership, unitTracker);
    }
    replicationVisitor.clean();
    double nodeChange = unitTracker.calculateUnitChange(newUnitMult, optTokenOwnership);
    return -(tokenChange + nodeChange);
}

Example 47 with Token

use of org.apache.cassandra.dht.Token in project cassandra by apache.

the class ReplicationAwareTokenAllocator method confirmCandidate.

/**
     * Incorporates the selected candidate into the ring, adjusting ownership information and calculated token
     * information.
     */
private void confirmCandidate(CandidateInfo<Unit> candidate) {
    // This process is less efficient than it could be (loops through each vnode's replication span instead
    // of recalculating replicationStart, replicationThreshold from existing data + new token data in an O(1)
    // case analysis similar to evaluateImprovement). This is fine as the method does not dominate processing
    // time.
    // Put the accepted candidate in the token list.
    UnitInfo<Unit> newUnit = candidate.owningUnit;
    Token newToken = candidate.token;
    sortedTokens.put(newToken, newUnit.unit);
    unitToTokens.put(newUnit.unit, newToken);
    TokenInfo<Unit> prev = candidate.prevInRing();
    TokenInfo<Unit> newTokenInfo = new TokenInfo<>(newToken, newUnit);
    newTokenInfo.replicatedOwnership = candidate.replicatedOwnership;
    // List is not empty so this won't need to change head of list.
    newTokenInfo.insertAfter(prev, prev);
    // Update data for candidate.
    populateTokenInfoAndAdjustUnit(newTokenInfo, newUnit.group);
    ReplicationVisitor replicationVisitor = new ReplicationVisitor();
    assert newTokenInfo.next == candidate.split;
    for (TokenInfo<Unit> curr = newTokenInfo.next; !replicationVisitor.visitedAll(); curr = curr.next) {
        // update the candidate between curr and next
        candidate = candidate.next;
        populateCandidate(candidate);
        if (!replicationVisitor.add(curr.owningUnit.group))
            // If we've already seen this group, the token cannot be affected.
            continue;
        populateTokenInfoAndAdjustUnit(curr, newUnit.group);
    }
    replicationVisitor.clean();
}

Example 48 with Token

use of org.apache.cassandra.dht.Token in project cassandra by apache.

the class TokenAllocation method evaluateReplicatedOwnership.

// return the ratio of ownership for each endpoint
public static Map<InetAddress, Double> evaluateReplicatedOwnership(TokenMetadata tokenMetadata, AbstractReplicationStrategy rs) {
    Map<InetAddress, Double> ownership = Maps.newHashMap();
    List<Token> sortedTokens = tokenMetadata.sortedTokens();
    Iterator<Token> it = sortedTokens.iterator();
    Token current = it.next();
    while (it.hasNext()) {
        Token next = it.next();
        addOwnership(tokenMetadata, rs, current, next, ownership);
        current = next;
    }
    addOwnership(tokenMetadata, rs, current, sortedTokens.get(0), ownership);
    return ownership;
}

Example 49 with Token

use of org.apache.cassandra.dht.Token in project cassandra by apache.

the class TokenAllocation method allocateTokens.

public static Collection<Token> allocateTokens(final TokenMetadata tokenMetadata, final AbstractReplicationStrategy rs, final InetAddress endpoint, int numTokens) {
    TokenMetadata tokenMetadataCopy = tokenMetadata.cloneOnlyTokenMap();
    StrategyAdapter strategy = getStrategy(tokenMetadataCopy, rs, endpoint);
    Collection<Token> tokens = create(tokenMetadata, strategy).addUnit(endpoint, numTokens);
    tokens = adjustForCrossDatacenterClashes(tokenMetadata, strategy, tokens);
    if (logger.isWarnEnabled()) {
        logger.warn("Selected tokens {}", tokens);
        SummaryStatistics os = replicatedOwnershipStats(tokenMetadataCopy, rs, endpoint);
        tokenMetadataCopy.updateNormalTokens(tokens, endpoint);
        SummaryStatistics ns = replicatedOwnershipStats(tokenMetadataCopy, rs, endpoint);
        logger.warn("Replicated node load in datacentre before allocation {}", statToString(os));
        logger.warn("Replicated node load in datacentre after allocation {}", statToString(ns));
        // TODO: Is it worth doing the replicated ownership calculation always to be able to raise this alarm?
        if (ns.getStandardDeviation() > os.getStandardDeviation())
            logger.warn("Unexpected growth in standard deviation after allocation.");
    }
    return tokens;
}

Example 50 with Token

use of org.apache.cassandra.dht.Token in project cassandra by apache.

the class TokenAllocation method adjustForCrossDatacenterClashes.

private static Collection<Token> adjustForCrossDatacenterClashes(final TokenMetadata tokenMetadata, StrategyAdapter strategy, Collection<Token> tokens) {
    List<Token> filtered = Lists.newArrayListWithCapacity(tokens.size());
    for (Token t : tokens) {
        while (tokenMetadata.getEndpoint(t) != null) {
            InetAddress other = tokenMetadata.getEndpoint(t);
            if (strategy.inAllocationRing(other))
                throw new ConfigurationException(String.format("Allocated token %s already assigned to node %s. Is another node also allocating tokens?", t, other));
            t = t.increaseSlightly();
        }
        filtered.add(t);
    }
    return filtered;
}