Rpk self test (#599)

Co-authored-by: Joyce Fee <102751339+Feediver1@users.noreply.github.com>
Co-authored-by: Kat Batuigas <36839689+kbatuigas@users.noreply.github.com>

modules/reference/pages/rpk/rpk-cluster/rpk-cluster-self-test-start.adoc

@@ -3,6 +3,8 @@
 
 Starts one or more benchmark tests on one or more nodes of the cluster.
 
+NOTE: Redpanda self-test runs benchmarks that consume significant system resources. Do not start self-test if large workloads are already running on the system. 
+
 Available tests to run:
 
 * *Disk tests*
@@ -14,17 +16,17 @@ Available tests to run:
 ** Throughput test: 8192-bit messages
 *** Unique pairs of Redpanda nodes each act as a client and a server.
 *** The test pushes as much data over the wire, within the test parameters.
-* *Cloud tests*
+* *Cloud storage tests*
 ** Latency test: 1024-bit object.
 ** Depending on cluster read/write permissions (xref:reference:properties/object-storage-properties.adoc#cloud_storage_enable_remote_read[`cloud_storage_enable_remote_read`], xref:reference:properties/object-storage-properties.adoc#cloud_storage_enable_remote_write[`cloud_storage_enable_remote_write`]), a series of cloud storage operations are performed:
 *** Upload an object to an object storage.
 *** List objects in the object storage.
 *** Download an object from the object storage.
 *** Delete the original object from the object storage, if it was uploaded.
 
-This command immediately returns on success, and the tests run asynchronously. The
-user polls for results with the xref:./rpk-cluster-self-test-status.adoc[rpk cluster self-test status]
-command.
+This command prompts users for confirmation (unless the flag `--no-confirm` is specified), then returns a test identifier ID, and runs the tests.
+
+To view the test status, poll xref:./rpk-cluster-self-test-status.adoc[rpk cluster self-test status]. Once the tests end, the cached results will be available with `rpk cluster self-test status`.
 
 == Usage
 
@@ -39,21 +41,27 @@ rpk cluster self-test start [flags]
 |===
 |*Value* |*Type* |*Description*
 
-|--disk-duration-ms |duration |uint The in milliseconds of individual
-disk test runs (default 30000).
+|--cloud-backoff-ms |uint | The backoff in milliseconds for a cloud storage request (default `100`).
+
+|--cloud-timeout-ms |uint | The timeout in milliseconds for a cloud storage request (default `5000`).
+
+|--disk-duration-ms |uint | The duration in milliseconds of individual
+disk test runs (default `30000`).
 
 |-h, --help |- |Help for start.
 
-|--network-duration-ms |duration |uint The in milliseconds of individual
-network test runs (default 30000).
+|--network-duration-ms |uint | The duration in milliseconds of individual
+network test runs (default `30000`).
 
 |--no-confirm |- |Acknowledge warning prompt skipping read from stdin.
 
+|--only-cloud-test |- |Runs only cloud storage benchmarks.
+
 |--only-disk-test |- |Runs only the disk benchmarks.
 
 |--only-network-test |- |Runs only network benchmarks.
 
-|--participant-node-ids |- |ints IDs of nodes that the tests will run
+|--participant-node-ids |uints |Comma-separated list of broker IDs that the tests will run
 on. If not set, tests will run for all node IDs.
 
 |--config |string |Redpanda or `rpk` config file; default search paths are `/var/lib/redpanda/.config/rpk/rpk.yaml`, `$PWD/redpanda.yaml`, and `/etc/redpanda/redpanda.yaml`.