KAFKA-19618: the record-size and throughputarguments don't work in TestRaftServer

[Yunyung]

The record-size and throughput arguments don’t work in
TestRaftServer. The recordsPerSec and recordSize values are always
hard-coded.

• Fix recordsPerSec and recordSize values hard-coded issue
• Add "Required" description to command-line options to make it clear to
  users.

Reviewers: Chia-Ping Tsai chia7712@gmail.com

[Yunyung]

Some benchmark for reference:

Default throughput and record-size

bin/test-kraft-server-start.sh --config config/kraft.properties --replica-directory-id b8tRS7h4TJ2Vt43Dp85v2A
...
Throughput (bytes/second): 445430.81, Latency (ms): 20.0 p75 26.0 p99 29.0 p999
Throughput (bytes/second): 1065534.70, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 1540081.58, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 1914122.07, Latency (ms): 20.0 p75 26.0 p99 27.0 p999

Throughput = 20000

bin/test-kraft-server-start.sh --config config/kraft.properties --replica-directory-id b8tRS7h4TJ2Vt43Dp85v2A --throughput 20000
...
Throughput (bytes/second): 8.53, Latency (ms): 29.0 p75 29.0 p99 29.0 p999
Throughput (bytes/second): 734822.26, Latency (ms): 20.0 p75 26.0 p99 34.0 p999
Throughput (bytes/second): 1283868.42, Latency (ms): 20.0 p75 26.0 p99 31.0 p999
Throughput (bytes/second): 1710625.79, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 2051202.05, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 2330801.78, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 5120510.52, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 5120510.57, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 5120402.04, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 5120397.13, Latency (ms): 20.0 p75 26.0 p99 27.0 p999

record-size = 512

bin/test-kraft-server-start.sh --config config/kraft.properties --replica-directory-id b8tRS7h4TJ2Vt43Dp85v2A --record-size 512
...
Throughput (bytes/second): 17.07, Latency (ms): 31.0 p75 31.0 p99 31.0 p999
Throughput (bytes/second): 366489.44, Latency (ms): 20.0 p75 26.0 p99 40.0 p999
Throughput (bytes/second): 640950.14, Latency (ms): 20.0 p75 26.0 p99 35.0 p999
Throughput (bytes/second): 854959.16, Latency (ms): 20.0 p75 26.0 p99 31.0 p999
Throughput (bytes/second): 1025596.13, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 1165135.54, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 2560561.89, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 2560481.59, Latency (ms): 20.0 p75 26.0 p99 27.0 p999
Throughput (bytes/second): 2560357.61, Latency (ms): 20.0 p75 26.0 p99 27.0 p999

[chia7712]

Could you please use CommandLineUtils.checkRequiredArgs to check the existence in this PR?

[Yunyung]

Updated. Thanks.

Verification:

$ bin/test-kraft-server-start.sh
[2025-08-21 00:41:04,035] INFO Registered `kafka:type=kafka.Log4jController` MBean (kafka.utils.Log4jControllerRegistration$)
Standalone raft server for performance testing
Option                                  Description                           
------                                  -----------                           
--config <String: filename>             REQUIRED: The configured file         
--help                                  Print usage information.              
--record-size <Integer: size in bytes>  The size of each record (default: 256)
--replica-directory-id <String:         REQUIRED: The directory id of the     
  directory id>                           replica                             
--throughput <Integer: records/sec>     The number of records per second the  
                                          leader will write to the metadata   
                                          topic (default: 5000)               
--version                               Display Kafka version.                

$ bin/test-kraft-server-start.sh --config config/kraft.properties 
[2025-08-21 00:41:12,627] INFO Registered `kafka:type=kafka.Log4jController` MBean (kafka.utils.Log4jControllerRegistration$)
Missing required argument "[replica-directory-id]"
Option                                  Description                           
------                                  -----------                           
--config <String: filename>             REQUIRED: The configured file         
--help                                  Print usage information.              
--record-size <Integer: size in bytes>  The size of each record (default: 256)
--replica-directory-id <String:         REQUIRED: The directory id of the     
  directory id>                           replica                             
--throughput <Integer: records/sec>     The number of records per second the  
                                          leader will write to the metadata   
                                          topic (default: 5000)               
--version                               Display Kafka version.                

$ bin/test-kraft-server-start.sh --replica-directory-id b8tRS7h4TJ2Vt43Dp85v2A
[2025-08-21 00:41:22,486] INFO Registered `kafka:type=kafka.Log4jController` MBean (kafka.utils.Log4jControllerRegistration$)
Missing required argument "[config]"
Option                                  Description                           
------                                  -----------                           
--config <String: filename>             REQUIRED: The configured file         
--help                                  Print usage information.              
--record-size <Integer: size in bytes>  The size of each record (default: 256)
--replica-directory-id <String:         REQUIRED: The directory id of the     
  directory id>                           replica                             
--throughput <Integer: records/sec>     The number of records per second the  
                                          leader will write to the metadata   
                                          topic (default: 5000)               
--version                               Display Kafka version.