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xqute.scheduler

module

xqute.scheduler

The scheduler to schedule jobs

Classes
  • Scheduler(workdir, forks, error_strategy, num_retries, prescript, postscript, jobname_prefix, submission_batch, recheck_interval, cwd, **kwargs) The abstract class for scheduler</>
abstract class

xqute.scheduler.Scheduler(workdir, forks=1, error_strategy='ignore', num_retries=3, prescript='', postscript='', jobname_prefix=None, submission_batch=None, recheck_interval=600, cwd=None, **kwargs)

The abstract class for scheduler

Attributes
  • jobcmd_wrapper_init The init script for the job command wrapper
  • jobcmd_wrapper_init (str) The init script for the job command wrapper</>
  • name The name of the scheduler
Parameters
  • workdir (str | pathlib.path | cloudpathlib.cloudpath.cloudpath) The working directory
  • forks (int, optional) Max number of job forks
  • error_strategy (str, optional) The strategy when there is error happened
  • num_retries (int, optional) Max number of retries when error_strategy is retry
  • prescript (str, optional) The prescript to run before the job commandIt is a piece of script that inserted into the wrapper script, running on the scheduler system.
  • postscript (str, optional) The postscript to run when job finishedIt is a piece of script that inserted into the wrapper script, running on the scheduler system.
  • jobname_prefix (str | none, optional) The prefix for the job name
  • submission_batch (int | none, optional) The number of consumers to submit jobs. This allowsmultiple jobs to be submitted in parallel. This is useful when there are many jobs to be submitted and the scheduler has a high latency for each submission. Set this to a smaller number if the scheduler cannot handle too many simultaneous submissions.
  • recheck_interval (int, optional) The number of polling iterations between rechecks ofwhether a job is still running on the scheduler. Helps detect jobs that fail before the wrapped script updates status (e.g., resource allocation failures). Each iteration takes ~0.1s, so default 600 means rechecking every ~60 seconds.
  • cwd (str | pathlib.path, optional) The working directory for the job command wrapper
  • **kwargs Other arguments for the scheduler
Methods
method

create_job(index, cmd, envs=None)

Create a job

Parameters
  • index (int) The index of the job
  • cmd (Union) The command of the job
Returns (Job)

The job

method

submit_job_and_update_status(job)

Submit and update the status

  1. Check if the job is already submitted or running
  2. If not, run the hook
  3. If the hook is not cancelled, clean the job
  4. Submit the job, raising an exception if it fails
  5. If the job is submitted successfully, update the status
  6. If the job fails to submit, update the status and write stderr to the job file
Parameters
  • job (Job) The job
method

retry_job(job)

Retry a job

Parameters
  • job (Job) The job
method

transition_job_status(job, new_status, rc=None, error_msg=None, is_killed=False)

Centralized status transition handler

Handles all aspects of job status transitions:

  • - Status change logging
  • - Hook lifecycle management (ensuring on_job_started is called)
  • - Appropriate hook calls based on new status
  • - RC file updates
  • - Error message appending to stderr
  • - JID file cleanup for terminal states
  • - Pipeline halt on errors if configured

Parameters
  • job (Job) The job to transition
  • new_status (int) The new status to transition to
  • rc (str | none, optional) Optional return code to write to rc_file
  • error_msg (str | none, optional) Optional error message to append to stderr_file
  • is_killed (bool, optional) Whether this is a killed job (uses on_job_killed hook)
method

kill_job_and_update_status(job)

Kill a job and update its status

Parameters
  • job (Job) The job
method

count_running_jobs(jobs)

Count currently running/active jobs (lightweight check)

This is optimized for the producer to check if new jobs can be submitted. It only counts jobs without refreshing status or calling hooks.

Parameters
  • jobs (List) The list of jobs
Returns (int)

Number of jobs currently in active states

method

check_all_done(jobs, polling_counter)

Check if all jobs are done (full polling with hooks)

This does complete status refresh and calls all lifecycle hooks. Used by the main polling loop to track job completion.

Parameters
  • jobs (List) The list of jobs
  • polling_counter (int) The polling counter for hook calls
Returns (bool)

True if all jobs are done, False otherwise

method

kill_running_jobs(jobs)

Try to kill all running jobs

Parameters
  • jobs (List) The list of jobs
method

job_is_submitted_or_running(job)

Check if a job is already submitted or running

Parameters
  • job (Job) The job
Returns (bool)

True if yes otherwise False.

method

job_fails_before_running(job)

Check if a job fails before running.

For some schedulers, the job might fail before running (after submission). For example, the job might fail to allocate resources. In such a case, the wrapped script might not be executed, and the job status will not be updated (stays in SUBMITTED). We need to check such jobs and mark them as FAILED.

For the instant scheduler, for example, the local scheduler, the failure will be immediately reported when submitting the job, so we don't need to check such jobs.

Parameters
  • job (Job) The job to check
Returns (bool)

True if the job fails before running, otherwise False.

method

jobcmd_shebang(job) → str

The shebang of the wrapper script

method

jobcmd_init(job) → str

The job command init

method

jobcmd_prep(job) → str

The job command preparation

method

jobcmd_end(job) → str

The job command end

method

wrap_job_script(job)

Wrap the job script

Parameters
  • job (Job) The job
Returns (str)

The wrapped script

method

wrapped_job_script(job)

Get the wrapped job script

Parameters
  • job (Job) The job
Returns (SpecPath)

The path of the wrapped job script

abstract method

submit_job(job)

Submit a job

Parameters
  • job (Job) The job
Returns (int | str)

The unique id in the scheduler system

abstract method

kill_job(job)

Kill a job

Parameters
  • job (Job) The job
abstract method

job_is_running(job)

Check if a job is really running

Parameters
  • job (Job) The job
Returns (bool)

True if yes otherwise False.