Java DatabaseDescriptor.getBatchlogReplayThrottleInKB方法代码示例

import org.apache.cassandra.config.DatabaseDescriptor; //导入方法依赖的package包/类
private void replayAllFailedBatches() throws ExecutionException, InterruptedException
{
    logger.debug("Started replayAllFailedBatches");

    // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
    // max rate is scaled by the number of nodes in the cluster (same as for HHOM - see CASSANDRA-5272).
    int throttleInKB = DatabaseDescriptor.getBatchlogReplayThrottleInKB() / StorageService.instance.getTokenMetadata().getAllEndpoints().size();
    RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);

    UntypedResultSet page = executeInternal(String.format("SELECT id, data, written_at, version FROM %s.%s LIMIT %d",
                                                          Keyspace.SYSTEM_KS,
                                                          SystemKeyspace.BATCHLOG_CF,
                                                          PAGE_SIZE));

    while (!page.isEmpty())
    {
        UUID id = processBatchlogPage(page, rateLimiter);

        if (page.size() < PAGE_SIZE)
            break; // we've exhausted the batchlog, next query would be empty.

        page = executeInternal(String.format("SELECT id, data, written_at, version FROM %s.%s WHERE token(id) > token(?) LIMIT %d",
                                             Keyspace.SYSTEM_KS,
                                             SystemKeyspace.BATCHLOG_CF,
                                             PAGE_SIZE),
                               id);
    }

    cleanup();

    logger.debug("Finished replayAllFailedBatches");
}
 

import org.apache.cassandra.config.DatabaseDescriptor; //导入方法依赖的package包/类
private void replayFailedBatches()
{
    logger.trace("Started replayFailedBatches");

    // rate limit is in bytes per second. Uses Double.MAX_VALUE if disabled (set to 0 in cassandra.yaml).
    // max rate is scaled by the number of nodes in the cluster (same as for HHOM - see CASSANDRA-5272).
    int endpointsCount = StorageService.instance.getTokenMetadata().getAllEndpoints().size();
    if (endpointsCount <= 0)
    {
        logger.trace("Replay cancelled as there are no peers in the ring.");
        return;
    }
    int throttleInKB = DatabaseDescriptor.getBatchlogReplayThrottleInKB() / endpointsCount;
    RateLimiter rateLimiter = RateLimiter.create(throttleInKB == 0 ? Double.MAX_VALUE : throttleInKB * 1024);

    UUID limitUuid = UUIDGen.maxTimeUUID(System.currentTimeMillis() - getBatchlogTimeout());
    ColumnFamilyStore store = Keyspace.open(SystemKeyspace.NAME).getColumnFamilyStore(SystemKeyspace.BATCHES);
    int pageSize = calculatePageSize(store);
    // There cannot be any live content where token(id) <= token(lastReplayedUuid) as every processed batch is
    // deleted, but the tombstoned content may still be present in the tables. To avoid walking over it we specify
    // token(id) > token(lastReplayedUuid) as part of the query.
    String query = String.format("SELECT id, mutations, version FROM %s.%s WHERE token(id) > token(?) AND token(id) <= token(?)",
                                 SystemKeyspace.NAME,
                                 SystemKeyspace.BATCHES);
    UntypedResultSet batches = executeInternalWithPaging(query, pageSize, lastReplayedUuid, limitUuid);
    processBatchlogEntries(batches, pageSize, rateLimiter);
    lastReplayedUuid = limitUuid;
    logger.trace("Finished replayFailedBatches");
}