通过 Pegasus shell 工具的 remote_command 命令向 Pegasus 集群发送远程命令，命令包含一个命令名和 0 个或多个参数，可以实现如信息收集、配置修改等功能。
通过远程命令执行操作有这些好处：
Pegasus 的不同角色（MetaServer、ReplicaServer）支持不同的远程命令。 可以通过 shell 工具的 remote_command help 命令 查看所有支持的命令。
获取 MetaServer 支持的远程命令，例如：
>>> remote_command -l 127.0.0.1:34601 help COMMAND: help CALL [user-specified] [127.0.0.1:34601] succeed: help|h|H|Help - Display help information repeat|r|R|Repeat - Execute a command periodically in every interval seconds for the max count time (0 for infinite) config-dump - Dump all configurations to a server local path or to stdout engine - Get engine internal information, including threadpools and threads and queues in each threadpool fd.allow_list - Show the allow list of failure detector flush-log - Flush log to stderr or file meta.live_percentage - node live percentage threshold for update perf-counters - Query perf counters, filtered by OR of POSIX basic regular expressions perf-counters-by-postfix - Query perf counters, filtered by OR of postfix strings perf-counters-by-prefix - Query perf counters, filtered by OR of prefix strings perf-counters-by-substr - Query perf counters, filtered by OR of substrs reset-log-start-level - Reset the log start level server-info - Query server information server-stat - Query selected perf counters system.queue - Get queue internal information, including the threadpool each queue belongs to, and the queue name and size task-code - Query task code containing any given keywords task.queue_max_length - Get the current or set a new max task queue length of a specific thread_pool. It can be set it to INT_MAX which means a big enough value, but it can't be cancelled the delay/reject policy dynamically Succeed count: 1 Failed count: 0
获取 ReplicaServer 支持的远程命令。例如：
>>> remote_command -l 127.0.0.1:34801 help COMMAND: help CALL [user-specified] [127.0.0.1:34801] succeed: help|h|H|Help - Display help information repeat|r|R|Repeat - Execute a command periodically in every interval seconds for the max count time (0 for infinite) config-dump - Dump all configurations to a server local path or to stdout engine - Get engine internal information, including threadpools and threads and queues in each threadpool flush-log - Flush log to stderr or file nfs.max_copy_rate_megabytes_per_disk - The maximum bandwidth (MB/s) of writing data per local disk when copying from remote node, 0 means no limit, should be greater than 'nfs_copy_block_bytes' which is 4194304 nfs.max_send_rate_megabytes_per_disk - The maximum bandwidth (MB/s) of reading data per local disk when transferring data to remote node, 0 means no limit perf-counters - Query perf counters, filtered by OR of POSIX basic regular expressions perf-counters-by-postfix - Query perf counters, filtered by OR of postfix strings perf-counters-by-prefix - Query perf counters, filtered by OR of prefix strings perf-counters-by-substr - Query perf counters, filtered by OR of substrs replica.deny-client - control if deny client read & write request replica.get-tcmalloc-status - Get the status of tcmalloc replica.kill_partition - Kill partitions by (all, one app, one partition) replica.max-concurrent-bulk-load-downloading-count - The maximum concurrent bulk load downloading replica count replica.mem-release-max-reserved-percentage - control tcmalloc max reserved but not-used memory percentage replica.query-app-envs - Query app envs on the underlying storage engine by app_id or app_id.partition_id replica.query-compact - Query full compact status on the underlying storage engine by app_id or app_id.partition_id replica.release-all-reserved-memory - Release tcmalloc all reserved-not-used memory back to operating system replica.release-tcmalloc-memory - control if try to release tcmalloc memory replica.trigger-checkpoint - Trigger replicas to do checkpoint by app_id or app_id.partition_id replica.verbose-client-log - control if print verbose error log when reply read & write request replica.verbose-commit-log - control if print verbose log when commit mutation reset-log-start-level - Reset the log start level server-info - Query server information server-stat - Query selected perf counters system.queue - Get queue internal information, including the threadpool each queue belongs to, and the queue name and size task-code - Query task code containing any given keywords task.queue_max_length - Get the current or set a new max task queue length of a specific thread_pool. It can be set it to INT_MAX which means a big enough value, but it can't be cancelled the delay/reject policy dynamically Succeed count: 1 Failed count: 0