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# Kudu bindings for YCSB

[Apache Kudu](https://kudu.apache.org) is a storage engine that enables fast
analytics on fast data.

## Benchmarking Kudu

Use the following command line to load the initial data into an existing Kudu
cluster with default configurations.

```
bin/ycsb load kudu -P workloads/workloada
```

Additional configurations:
* `kudu_master_addresses`: The master's address. The default configuration
  expects a master on localhost.
* `kudu_pre_split_num_tablets`: The number of tablets (or partitions) to create
  for the table. The default uses 4 tablets. A good rule of thumb is to use 5
  per tablet server.
* `kudu_table_num_replicas`: The number of replicas that each tablet will have.
  The default is 3. Should only be configured to use 1 instead, for single node tests.
* `kudu_sync_ops`: If the client should wait after every write operation. The
  default is true.
* `kudu_block_size`: The data block size used to configure columns. The default
  is 4096 bytes.

Then, you can run the workload:

```
bin/ycsb run kudu -P workloads/workloada
```

## Using a previous client version

If you wish to use a different Kudu client version than the one shipped with
YCSB, you can specify on the command line with `-Dkudu.version=x`. For example:

```
mvn -pl com.yahoo.ycsb:kudu-binding -am package -DskipTests -Dkudu.version=1.0.1
```

Note that only versions since 1.0 are supported, since Kudu did not guarantee
wire or API compatibility prior to 1.0.