parallel 命令

常用示例

说明

GNU Parallel runs jobs in parallel, utilizing multiple CPU cores. It's a more powerful replacement for xargs -P, designed for parallel processing of command-line tasks. Arguments can come from the command line (:::), files (::::), or stdin. The {} placeholder is replaced with each argument. Variants like {.} (no extension), {/} (basename), and {//} (dirname) enable flexible filename manipulation. Job control includes limiting parallelism (-j), distributing across SSH hosts (-S), and handling failures (--halt). Output can be kept in order (--keep-order) or saved to separate files (--results). For distributed computing, parallel copies necessary files to remote hosts, runs jobs, and retrieves output. This enables clusters without complex job schedulers. Progress tracking with --bar or --eta helps monitor long-running batch jobs. Logging options record what ran and what failed for later analysis.

参数

-j, --jobs _N_

Number of parallel jobs (N, N%, +N, -N).

-S, --sshlogin _HOSTS_

Remote hosts for distributed execution.

-a, --arg-file _FILE_

Read arguments from file.

:::, :::::

Argument separators (inline or from file).

{}

Replacement string for argument.

{#}

Job number.

{%}

Job slot number.

{.}

Argument without extension.

{/}

Basename of argument.

{//}

Directory of argument.

--bar

Show progress bar.

--eta

Show estimated time of arrival.

--dry-run

Show commands without executing.

--keep-order, -k

Preserve output order.

--halt _MODE_

When to halt: never, soon, now.

--results _DIR_

Save output to files in directory.

--delay _TIME_

Delay between job starts.

--retries _N_

Retry failed jobs.

--timeout _TIME_

Maximum runtime per job.