package org.kududb.ts.core;
import com.google.common.collect.ImmutableList;
import org.apache.kudu.ColumnSchema;
import org.apache.kudu.Schema;
import org.apache.kudu.Type;
import org.apache.kudu.annotations.InterfaceAudience;
import org.apache.kudu.client.CreateTableOptions;
import org.apache.kudu.client.PartialRow;
/**
* {@code Tables} holds meta information about the table schemas used by {@code KuduTS}.
*/
@InterfaceAudience.Private
class Tables {
private Tables() {}
static final int METRICS_METRIC_INDEX = 0;
static final int METRICS_TAGSET_ID_INDEX = 1;
static final int METRICS_TIME_INDEX = 2;
static final int METRICS_VALUE_INDEX = 3;
static final int TAGSETS_ID_INDEX = 0;
static final int TAGSETS_TAGSET_INDEX = 1;
static final int TAGS_KEY_INDEX = 0;
static final int TAGS_VALUE_INDEX = 1;
static final int TAGS_TAGSET_ID_INDEX = 2;
static final ColumnSchema METRICS_METRIC_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("metric", Type.STRING)
.nullable(false)
.key(true)
.encoding(ColumnSchema.Encoding.DICT_ENCODING).build();
static final ColumnSchema METRICS_TAGSET_ID_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("tagset_id", Type.INT32)
.nullable(false)
.key(true)
.compressionAlgorithm(ColumnSchema.CompressionAlgorithm.LZ4)
.build();
static final ColumnSchema METRICS_TIME_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("time", Type.UNIXTIME_MICROS)
.nullable(false)
.key(true)
.encoding(ColumnSchema.Encoding.BIT_SHUFFLE)
.build();
static final ColumnSchema METRICS_VALUE_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("value", Type.DOUBLE)
.nullable(false)
.encoding(ColumnSchema.Encoding.BIT_SHUFFLE)
.build();
static final ColumnSchema TAGSETS_ID_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("id", Type.INT32)
.nullable(false)
.key(true).build();
static final ColumnSchema TAGSETS_TAGSET_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("tagset", Type.BINARY)
.nullable(false)
.compressionAlgorithm(ColumnSchema.CompressionAlgorithm.LZ4)
.build();
static final ColumnSchema TAGS_KEY_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("key", Type.STRING)
.nullable(false)
.key(true)
.encoding(ColumnSchema.Encoding.DICT_ENCODING)
.build();
static final ColumnSchema TAGS_VALUE_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("value", Type.STRING)
.nullable(false)
.key(true)
.encoding(ColumnSchema.Encoding.DICT_ENCODING)
.build();
static final ColumnSchema TAGS_TAGSET_ID_COLUMN =
new ColumnSchema.ColumnSchemaBuilder("tagset_id", Type.INT32)
.nullable(false)
.key(true)
.build();
static final Schema METRICS_SCHEMA = new Schema(ImmutableList.of(METRICS_METRIC_COLUMN,
METRICS_TAGSET_ID_COLUMN,
METRICS_TIME_COLUMN,
METRICS_VALUE_COLUMN));
static final Schema TAGSETS_SCHEMA = new Schema(ImmutableList.of(TAGSETS_ID_COLUMN,
TAGSETS_TAGSET_COLUMN));
static final Schema TAGS_SCHEMA = new Schema(ImmutableList.of(TAGS_KEY_COLUMN,
TAGS_VALUE_COLUMN,
TAGS_TAGSET_ID_COLUMN));
static String metricsTableName(String tsName) {
return String.format("kuduts.%s.metrics", tsName);
}
static String tagsetsTableName(String tsName) {
return String.format("kuduts.%s.tagsets", tsName);
}
static String tagsTableName(String tsName) {
return String.format("kuduts.%s.tags", tsName);
}
/**
* The {@code metrics} table is hash partitioned on the {@code metric} and
* {@code tagset_id} columns, and range partitioned on the {@code time}
* column. The hash partitioning allows writes and scans at the current time
* to be evenly distributed over the cluster. Range partitioning on time
* allows whole tablets to be pruned based on the time constraint, and allows
* old data to be dropped if desired.
* @param options the create options
* @param numTabletServers the number of tablet servers
* @return the tags table create options
*/
static CreateTableOptions metricsCreateTableOptions(CreateOptions options,
int numTabletServers) {
CreateTableOptions create = new CreateTableOptions();
create.setNumReplicas(options.getNumReplicas());
create.addHashPartitions(ImmutableList.of("metric", "tagset_id"),
options.getNumMetricsHashBuckets(numTabletServers));
create.setRangePartitionColumns(ImmutableList.of("time"));
for (Long time : options.getMetricsSplits()) {
PartialRow split = METRICS_SCHEMA.newPartialRow();
split.addLong(METRICS_TIME_INDEX, time);
create.addSplitRow(split);
}
return create;
}
/**
* The {@code tagsets} table is range partitioned on the {@code id} column.
* Because the table is essentially a linear probe hash table, it must be able
* to be scanned in PK order, so hash partitioning is not possible. Since the
* tagset IDs are effectively random, setting split points at even intervals
* over the ID range gives good protection against hotspotting.
* @param options the create options
* @param numTabletServers the number of tablet servers
* @return the tagset table create options
*/
static CreateTableOptions tagsetsCreateTableOptions(CreateOptions options,
int numTabletServers) {
CreateTableOptions create = new CreateTableOptions();
create.setNumReplicas(options.getNumReplicas());
create.setRangePartitionColumns(ImmutableList.of("id"));
int numTablets = options.getNumTagsetsTablets(numTabletServers);
long interval = (1L << 32) / numTablets;
for (int i = 1; i < numTablets; i++) {
PartialRow split = TAGSETS_SCHEMA.newPartialRow();
split.addInt(TAGSETS_ID_INDEX, (int) (Integer.MIN_VALUE + i * interval));
create.addSplitRow(split);
}
return create;
}
/**
* The {@code tags} table is hash partitioned on the {@code key} and
* {@code value} columns, which allows a scan of a ({@code key}, {@code value})
* pair to be fully satisfied by a single tablet, and gives good protection
* against hotspotting.
* @param options the create options
* @param numTabletServers the number of tablet servers
* @return the tags table create options
*/
static CreateTableOptions tagsCreateTableOptions(CreateOptions options,
int numTabletServers) {
CreateTableOptions create = new CreateTableOptions();
create.setNumReplicas(options.getNumReplicas());
create.addHashPartitions(ImmutableList.of("key", "value"),
options.getNumTagsTablets(numTabletServers));
create.setRangePartitionColumns(ImmutableList.<String>of());
return create;
}
}
