Couchbase C Client  2.6.2
cbc-pillowfight(1) - Stress Test for Couchbase Client and Cluster


cbc-pillowfight [OPTIONS]


cbc-pillowfight creates a specified number of threads each looping and performing get and set operations within the cluster.

The stress test operates in the following order

  1. It will pre-load the items in the cluster (set by the --num-items option)
  2. Once the items are all loaded into the cluster, it will access all the items (within the --num-items) specification, using a combination of storage and retrieval operations (the proportion of retrieval and storage operations are controlled via the --set-pct option).
  3. Operations are scheduled in batches. The batches represent a single pipeline (or network buffer) which is filled with a certain amount of operations (see the --batch-size option). These batch sizes are then sent over to the cluster and the requests are serviced by it.


Getting the right benchmark numbers highly depends on the type of environment the client is being run in. The following provides some information about specific settings which may make pillowfight generate more operations.

  • Increasing the batch size will typically speed up operations, but increasing the batch size too much will actually slow it down. Additionally, very high batch sizes will cause high memory usage.
  • Adding additional threads will create additional client objects and connections, potentially increasing performance. Adding too many threads will cause local and network resource congestion.
  • Decreasing the item sizes (the --min-size and --max-size options) will always yield higher performance in terms of operationd-per-second.
  • Limiting the working set (i.e. --num-items) will decrease the working set within the cluster, thereby increasing the chance that a given item will be inside the server's CPU cache (which is extremely fast), rather than in main memory (slower), or disk (much slower)


Options may be read either from the command line, or from a configuration file (see cbcrc(4)):

The following options control workload generation:

  • -B, --batch-size=_BATCHSIZE_: This controls how many commands are scheduled per cycles. To simulate one operation at a time, set this value to 1.
  • -I, --num-items=_NUMITEMS_: Set the total number of items the workload will access within the cluster. This will also determine the working set size at the server and may affect disk latencies if set to a high number.
  • -p, --key-prefix=_PREFIX_: Set the prefix to prepend to all keys in the cluster. Useful if you do not wish the items to conflict with existing data.
  • -t, --num-threads=_NTHREADS_: Set the number of threads (and thus the number of client instances) to run concurrently. Each thread is assigned its own client object.
  • -r, --set-pct=_PERCENTAGE_: The percentage of operations which should be mutations. A value of 100 means only mutations while a value of 0 means only retrievals.
  • -n, --no-population: By default cbc-pillowfight will load all the items (see --num-items) into the cluster and then begin performing the normal workload. Specifying this option bypasses this stage. Useful if the items have already been loaded in a previous run.
  • -m, --min-size=_MINSIZE_:
  • -M, --max-size=_MAXSIZE_: Specify the minimum and maximum value sizes to be stored into the cluster. This is typically a range, in which case each value generated will be between --min-size and --max-size bytes.
  • -E, --pause-at-end: When the workload completes, do not exit immediately, but wait for user input. This is helpful for analyzing open socket connections and state.
  • -c, --num-cycles: Specify the number of times the workload should cycle. During each cycle an amount of --batch-size operations are executed. Setting this to -1 will cause the workload to run infinitely.
  • --sequential: Specify that the access pattern should be done in a sequential manner. This is useful for bulk-loading many documents in a single server.
  • --start-at: This specifies the starting offset for the items. The items by default are generated with the key prefix (--key-prefix) up to the number of items (--num-items). The --start-at value will increase the lower limit of the items. This is useful to resume a previously cancelled load operation.
  • -T, --timings: Dump a histogram of command timings and latencies to the screen every second.
  • -e, --expiry=_SECONDS_: Set the expiration time on the document for SECONDS when performing each operation. Note that setting this too low may cause not-found errors to appear on the screen.
  • -U, --spec=_SPEC_: A string describing the cluster to connect to. The string is in a URI-like syntax, and may also contain other options. See the EXAMPLES section for information. Typically such a URI will look like couchbase://host1,host2,host3/bucket.

    The default for this option is couchbase://localhost/default

  • -P, --password=_SASLPASS_:
  • -P -, --password=-: Specify the SASL password for the bucket. This is only needed if the bucket is protected with a password. Note that this is not the administrative password used to log into the web interface.

    Specifying the - as the password indicates that the program should prompt for the password. You may also specify the password on the commandline, directly, but is insecure as command line arguments are visible via commands such as ps.

  • -T, --timings: Dump command timings at the end of execution. This will display a histogram showing the latencies for the commands executed.
  • -v, --verbose: Specify more information to standard error about what the client is doing. You may specify this option multiple times for increased output detail.
  • -D, --cparam=OPTION=VALUE: Provide additional client options. Acceptable options can also be placed in the connection string, however this option is provided as a convenience. This option may be specified multiple times, each time specifying a key=value pair (for example, -Doperation_timeout=10 -Dconfig_cache=/foo/bar/baz). See ADDITIONAL OPTIONS for more information
  • --json: Make pillowfight store document as JSON rather than binary. This will allow the documents to nominally be analyzed by other Couchbase services such as Query and MapReduce.

    JSON documents are created by creating an empty JSON object ({}) and then repeated populating it with Field_d property names (where d is 1 and higher), and setting its value to a repeating asterisk * up to 16 times:

          "Field_1": "****************",
          "Field_2": "****************",
          "Field_3": "****************",
          "Field_4": "****************",
          "Field_5": "********"

    When using document size constraints, be aware that the minimum and maximum sizes (--min-size and --max-size) are not strict limits, and that the resultant sizes may be bigger or smaller by a few bytes in order to satisfy the requirements of proper JSON syntax.

  • --subdoc: Use couchbase sub-document operations when running the workload. In this mode pillowfight will use Couchbase sub-document operations to perform gets and sets of data. This option must be used with --json
  • --pathcount: Specify the number of paths a single sub-document operation should contain. By default, each subdoc operation operates on only a single path within the document. You can specify multiple paths to atomically executed multiple subdoc operations within a single command.

    This option does not affect the --batch-size option as a subdoc command is considered as a single command (with respect to batching) regardless of how many operations it contains.


The following options may be included in the connection string (via the -U option) as URI-style query params (e.g. couchbase://host/bucket?option1=value1&option2=value2) or as individual key=value pairs passed to the -D switch (e.g. -Doption1=value1 -Doption2=value). The -D will internally build the connection string, and is provided as a convenience for options to be easily passed on the command-line

  • operation_timeout=SECONDS: Specify the operation timeout in seconds. This is the time the client will wait for an operation to complete before timing it out. The default is 2.5
  • config_cache=PATH: Enables the client to make use of a file based configuration cache rather than connecting for the bootstrap operation. If the file does not exist, the client will first connect to the cluster and then cache the bootstrap information in the file.
  • certpath=PATH: The path to the server's SSL certificate. This is typically required for SSL connectivity unless the certificate has already been added to the openssl installation on the system (only applicable with couchbases:// scheme)
  • ssl=no_verify: Temporarily disable certificate verification for SSL (only applicable with couchbases:// scheme). This should only be used for quickly debugging SSL functionality.
  • sasl_mech_force=MECHANISM: Force a specific SASL mechanism to be used when performing the initial connection. This should only need to be modified for debugging purposes. The currently supported mechanisms are PLAIN and CRAM-MD5
  • bootstrap_on=<both,http,cccp>: Specify the bootstrap protocol the client should use when attempting to connect to the cluster. Options are: cccp: Bootstrap using the Memcached protocol (supported on clusters 2.5 and greater); http: Bootstrap using the HTTP REST protocol (supported on any cluster version); and both: First attempt bootstrap over the Memcached protocol, and use the HTTP protocol if Memcached bootstrap fails. The default is both



The following examples show how to connect pillowfight to different types of cluster configurations.

Run against a bucket (a_bucket) on a cluster on a remote host:

cbc cat key -U couchbase://

Connect to an SSL cluster at The certificate for the cluster is stored locally at /home/couchbase/couchbase_cert.pem:

cbc cat key -U couchbases://

Connect to an SSL cluster at, ignoring certificate verification. This is insecure but handy for testing:

cbc cat key -U couchbases://

Connect to a password protected bucket (protected) on a remote host:

cbc cat key -U couchbase:// -P -
Bucket password:

Connect to a password protected bucket, specifying the password on the command line (INSECURE, but useful for testing dummy environments)

cbc cat key -U couchbase:// -P t0ps3cr3t

Connect to a bucket running on a cluster with a custom REST API port

cbc cat key -U http://localhost:9000/default

Connec to bucket running on a cluster with a custom memcached port

cbc cat key -U couchbase://localhost:12000/default

Connect to a memcached ( cluster using the binary protocol. A vanilla memcached cluster is not the same as a memcached bucket residing within a couchbase cluster (use the normal couchbase:// scheme for that):

cbc cat key -U memcached://host1,host2,host3,host4

Connect to an SSL cluster at

cbc-pillowfight -U couchbases://

Run against a bucket (a_bucket) on a cluster on a remote host:

cbc-pillowfight -U couchbase://


The following examples show how to configure different types of workloads with pillowfight.

Run with 20 threads/instances, each doing one operation at a time:

cbc-pillowfight -t 20 -B 1

Run 100 iterations of 2MB item sizes, using a dataset of 50 items

cbc-pillowfight -M $(1024*1024) -m $(1024*1024) -c 100 -I 50

Use JSON documents of 100k each

cbc-pillowfight --json -m 100000 -M 100000

Stress-test sub-document mutations

cbc-pillowfight --json --subdoc --set-pct 100


Rather than spawning threads for multiple instances, offer a way to have multiple instances function cooperatively inside an event loop.


This command's options are subject to change.


cbc(1), cbcrc(4)


The cbc-pillowfight tool was first introduced in libcouchbase 2.0.7