wiki:Workshops/JobCheckpointing/Examples

Version 19 (modified by Carl Baribault, 3 months ago) ( diff )

Added link to MATLAB checkpointing example

Job Checkpointing Examples

Overview

This example implements a submitter/runner (also called cyclic checkpoint/restart) pattern.

Submitter -> Runner -> Application

A lightweight submitter job launches a runner job that in turn launches the application for a bounded time.

After that time, the application writes a checkpoint, and exits cleanly.

Submitter self-resubmits before timing out

The submitter itself also runs for a bounded time while monitoring progress. Just before timing out, the submitter resubmits a new submitter job as needed until the workflow completes using the sbatch command rather than the SLURM requeue feature. For details on this checkpointing implementation, see Checkpoint workflow implementation below.

Why do we use sbatch vs SLURM requeue?

Unacceptable use of requeue

The SLURM resource manager provides an option to requeue a running job via the command scontrol requeue. (See man scontrol.)

However, when a job is requeued, any previous record of elapsed time used by that same job is overwritten.

Hence, the requeue option has the following 2 consequences.

  1. You would not be able to track the total elapsed time used by your requeued job.
  2. As a result, your job would be in violation of Tulane Information Technology's Acceptable Use Policy, including your consent to monitor your use of Cypress.

Before you adopt checkpointing

Before you adopt a checkpointing workflow, make a determination of whether your workflow consists - either entirely or in large part - of data elements or other components that can be processed entirely independently of each other - rather than each element depending on the result of the previous. This is also referred to as embarrassingly parallel. (See also Embarrassingly Parallel Algorithms Explained.)

In order to make the above determination, you may need to consult your software provider's user forum, such as GitHub.

In case your workflow is embarrassingly parallel, then please first refer to the material in Job Parallelism.

Quick start

For a quick start using checkpointing, see Working Examples below.

Background on checkpointing

Use checkpointing for sequential workflows

This checkpointing implementation should be used for running sequential workflows on Cypress - where each component result of the workflow depends the previous component result in the workflow. (See above Before you adopt checkpointing.)

Checkpointing - an HPC workflow design pattern

This checkpointing implementation can be considered an implementation of an HPC workflow design pattern (see for example Design Patterns) that can be described by any of the following expressions.

How does the workflow determine when to stop?

Limiting the work: using the sbatch --dependencies option

Note that in the context of the last reference in the above list - using job dependencies, when you use the SLURM sbatch --dependencies... option, the stopping point is not determined automatically.

You may need additional effort to determine the precise number of sbatch --dependencies... commands to exiecute - in other words, to determine the length of the dependency chain - before starting the workflow.

Limiting the work: using the application's own work limit

This implementation differs from the above dependency chain, in that rather than using the sbatch --dependencies option, the stopping point is determined automatically during runtime.

In this implementation, the workflow self restarts or resumes as needed and self terminates when the application's work limit is reached - in other words when the application's work is done. See for example the setting MAX_ITER in checkpoint_submitter.sh below.

Checkpoint workflow implementation

Execution Model (Diagram)

+-----------+               +-----------+             +---------------+
| Submitter |               |  Runner   |             |  Application  |
|  (job)    |               |   (job)   |             |   (process)   |
+-----------+               +-----------+             +---------------+
      |                           |                           |
      |  if Application not done, |                           |
      |  submit(sbatch)           |                           |
      | ------------------------> |                           |
      |  otherwise, exit          |        run                |
      |                           | ------------------------> |
      |                           |                           |
      | ----+                     |    SIGTERM @ timeout      |
      |     | wait for self       | ------------------------> |
      |     | timeout             |                           | ----+
      |     |                     |                           |     |
      |     |                     |                           |     | handle SIGTERM
      |     |                     |                           |     | & write checkpoint
      |     |                     |                           | <---+
      |     |                     |           exit code       |
      |     |                     + <-------------------------+
      |     |        Runner exit (progress / done / failure)
      | <---+
      |
      | update workflow state
      | submit new Submitter
      | interpret Runner exit code
      + exit

(Submitter state persisted e.g. to submitter_state.txt)

Components explained

In this implementation, the checkpointing workflow consists of the following components.

  1. the checkpoint submitter - to perform the following
    1. self restart as needed, and
    2. re-submit the runner once per self-restart
  2. the checkpoint runner - to perform the following
    1. set its own application timer via the timeout command
    2. re-start the application as needed
    3. send the signal SIGTERM to the application at timeout
  3. the checkpoint application - to perform the following
    1. compute
    2. catch the runner's signal SIGTERM
    3. "handle" the runner's signal SIGTERM by quickly saving the work and stop running (See Working Examples for applications in BASH, Python and R.)

Checkpoint Submitter

Here is the job script for the checkpoint submitter, a fully self-restarting job that controls the workflow by self-restarting as many times as needed and submitting one instance per each restart of the checkpoint runner job script. (See Checkpoint Runner further below.)

Overriding default settings

This checkpoint submitter uses settings - with default values - implemented using environment variables (see Environment Variables), where the default values can be overridden by either of the following.

  1. Override default settings by one or more export commands prior to the sbatch command

# example: export all on one line, then submit
[tulaneId@cypress1 ~]$export VAR1=<value1> VAR2=<value2> ...
[tulaneId@cypress1 ~]$sbatch checkpoint_submitter.sh
# example: or export one line for each variable, then submit
[tulaneId@cypress1 ~]$export VAR1=<value1>
[tulaneId@cypress1 ~]$export VAR2=<value2>
...
[tulaneId@cypress1 ~]$sbatch checkpoint_submitter.sh

  1. Alternatively, override settings by assigning values at the beginning, in front of the sbatch command
# example: all on one line with submit
[tulaneId@cypress1 ~]$VAR1=<value1> VAR2=<value2> ... sbatch checkpoint_submitter.sh
# example: on multiple lines using the line continuation character "\" with submit
[tulaneId@cypress1 ~]$VAR1=<value1> \
VAR2=<value2> \
... \
sbatch checkpoint_submitter.sh

checkpoint_submitter.sh

#!/bin/bash
###############################################################################
# CHECKPOINT SUBMITTER: self-restarting to re-submit runner
# Controls repeated submissions of checkpoint_runner.sh
###############################################################################
# User settings with defaults
###############################################################################
# CKPT_PATH            : path to checkpoint file
# MAX_ITER             : stop application after this many iterations total
# RUNNER_SCRIPT        : job script with checkpoint before end of time limit
# SUBMITTER_MARGIN_SEC : time margin to restart before time limit
# SUBMITTER_TIME_LIMIT : wall time <= 24 hours (format as --time in man sbatch)
###############################################################################
# Edit settings below
# Or pass values via...
#   sbatch --export=ALL,Var1=...,...,VarN=... checkpoint_submitter.sh
# Or pass values via...
#   Var1=... VarN=... sbatch checkpoint_submitter.sh
###############################################################################
CKPT_PATH="${CKPT_PATH:-state_iter.txt}"
MAX_ITER="${MAX_ITER:-500}"
RUNNER_SCRIPT="${RUNNER_SCRIPT:-checkpoint_runner.sh}"
SUBMITTER_MARGIN_SEC="${SUBMITTER_MARGIN_SEC:-60}"
SUBMITTER_TIME_LIMIT="${SUBMITTER_TIME_LIMIT:-3:30}"
###############################################################################
# Slurm directives (keep SUBMITTER_TIME_LIMIT <= 24 hours)
###############################################################################
#SBATCH --job-name=ckpt_submitter
#SBATCH --output=log_submitter_%j.out
#SBATCH --error=log_submitter_%j.err
#SBATCH --time=24:00:00
#SBATCH --ntasks=1
#SBATCH --cpus-per-task=1
#SBATCH --mem=256M
#SBATCH --partition=centos7
#SBATCH --qos=normal
###############################################################################
# Exit on error
###############################################################################
set -euo pipefail
###############################################################################
# Helpers
###############################################################################
shopt -s expand_aliases
alias dtstamp='date +%Y%m%d-%H:%M:%S'
info(){ echo "Info[$(dtstamp)]: $*"; }
get_ckpt_iter() {
  [[ -f "${CKPT_PATH}" ]] || { echo 0; return; }
  tr -cd '0-9' < "${CKPT_PATH}" 2>/dev/null || echo 0
}
submit_worker() {
  sbatch "${RUNNER_SCRIPT}" | awk '{print $4}'
}
to_seconds() {
        # Acceptable time formats include "minutes", "minutes:seconds", "hours:min- utes:seconds",
        # "days-hours", "days-hours:minutes" and "days-hours:minutes:seconds"
        local input="$1"
        # Handle days-hours format by replacing '-' with ':' to unify the delimiter
        # Then split components into an array
        IFS=':' read -r -a parts <<< "${input//-/:}"
        case ${#parts[@]} in
            1) # Format: minutes
                seconds=$((parts[0] * 60))
                ;;
            2) # Formats: minutes:seconds OR days-hours
                if [[ $input == *"-"* ]]; then
                    seconds=$((parts[0] * 86400 + parts[1] * 3600))
                else
                    seconds=$((parts[0] * 60 + parts[1]))
                fi
                ;;
            3) # Formats: hours:minutes:seconds OR days-hours:minutes
                if [[ $input == *"-"* ]]; then
                    seconds=$((parts[0] * 86400 + parts[1] * 3600 + parts[2] * 60))
                else
                    seconds=$((parts[0] * 3600 + parts[1] * 60 + parts[2]))
                fi
                ;;
            4) # Format: days-hours:minutes:seconds
                seconds=$((parts[0] * 86400 + parts[1] * 3600 + parts[2] * 60 + parts[3]))
                ;;
            *)
                echo "Unsupported format"
                exit 1
                ;;
        esac
        echo "$seconds"
}
should_restart() {
  now=$(date +%s)
  elapsed=$(( now - restart_start_sec ))
  remaining=$(( restart_limit_sec - elapsed ))
  echo -ne "Time before restart: $remaining (sec)\r" >&2
  (( remaining < SUBMITTER_MARGIN_SEC ))
}
###############################################################################
# Log settings
###############################################################################
info "Start on $(hostname); JOBID=${SLURM_JOB_ID:-unknown}"
info "Submitter settings:"
info "CKPT_PATH=${CKPT_PATH}"
info "MAX_ITER=${MAX_ITER}"
info "RUNNER_SCRIPT=${RUNNER_SCRIPT}"
info "SUBMITTER_MARGIN_SEC=${SUBMITTER_MARGIN_SEC}"
info "SUBMITTER_TIME_LIMIT=${SUBMITTER_TIME_LIMIT}"
###############################################################################
# Restore state if present
###############################################################################
state_file="submitter_state.txt"
submitter_cycle=0
if [[ -f "${state_file}" ]]; then
  source "${state_file}"
  info "Loaded state: submitter_cycle=${submitter_cycle}"
else
  info "No previous state found; starting fresh."
fi
###############################################################################
# Track time for restart
###############################################################################
restart_start_sec=$(date +%s)
restart_limit_sec=$(to_seconds "${SUBMITTER_TIME_LIMIT}")
###############################################################################
# Main Loop
###############################################################################
info "Submitter cycle: ${submitter_cycle}"
module load anaconda3/2023.07 # using python3
while true; do
  current_iter=$(get_ckpt_iter)
  info "Current checkpoint iteration: ${current_iter}"
  if (( current_iter >= MAX_ITER )); then
          info "Reached MAX_ITER=${MAX_ITER}; running final analytics."
    # List of analytics scripts to check
    analytics_scripts=(
      "aggregate_usage.py"
      "plot_progress.py"
    )
          # Run resource usage aggregation
          if command -v python3 >/dev/null 2>&1; then
      # Loop over each script and run only if present
      for script in "${analytics_scripts[@]}"; do
        if [[ -f "${script}" ]]; then
          info "Running analytics ${script} ..."
          python3 "${script}"
        else
          info "WARNING: ${script} not found; skipping."
        fi
      done
          else
            info "WARNING: python3 not found; skipping analytics."
          fi
          info "Workflow complete. Exiting submitter."
    exit 0

  fi
  JOBID=$(submit_worker)
  info "Submitted worker: ${JOBID}"
        # Log worker JobIDs for later aggregation
        id_log="worker_ids.txt"
        echo "${JOBID}" >> "${id_log}"
  # Wait for worker to finish
  info "Waiting on first of worker ${JOBID} to finish or self-restart."
  while squeue -j "${JOBID}" >/dev/null 2>&1; do
    sleep 10
    if should_restart; then
      info "Submitter approaching timeout -> restarting self"
      # Save state
      echo "submitter_cycle=$((submitter_cycle+1))" > "${state_file}"
      # Submit a new submitter instance
      sbatch checkpoint_submitter.sh
      exit 0

    fi
  done
  # Read worker exit code
  rc=$(sacct -j "${JOBID}" --format=ExitCode -P | awk -F: 'NR==2{print $1}')
  info "Worker finished with code ${rc}"
  case "${rc}" in
    0)
      info "Worker reports completed workflow."
      exit 0

      ;;
    99|124)
      info "Checkpoint advance -> continuing workflow."
      ;;
    *)
      info "Unexpected worker failure (code ${rc}). Stopping."
      exit "${rc}"

      ;;
  esac
  # Loop continues to submit next worker
done

Checkpoint Runner

Here is the job script for the checkpoint runner to be used with the following.

checkpoint_runner.sh

#!/bin/bash
###############################################################################
# CHECKPOINT RUNNER: run application w/ checkpoint + controlled stop
# Use with checkpoint_submitter.sh to re-submit as needed
###############################################################################
# User settings with defaults
###############################################################################
# APP_CMD          : command to run (string) - must handle signal SIGTERM
# CHECKPOINT_EVERY : checkpoint after every this many application iterations
# CKPT_PATH        : path to checkpoint file
# LAUNCH_MODE      : run app command directly or via srun
# MAX_ITER         : stop application after this many iterations total
# MODULE_LIST      : modules loaded before running app command
# RUNNER_MARGIN_SEC: seconds before wall time to checkpoint (for timeout)
# RUNNER_TIME_LIMIT: wall time <= 24 hours (format as --time in man sbatch)
# SRUN_ARGS        : arguments to srun, if needed
###############################################################################
# Edit settings below
# Or pass values via...
#   sbatch --export=ALL,Var1=...,...,VarN=... checkpoint_submitter.sh
# Or pass values via...
#   Var1=... VarN=... sbatch checkpoint_submitter.sh
###############################################################################
APP_CMD="${APP_CMD:-python3 checkpoint_signal_iter.py}"
CHECKPOINT_EVERY="${CHECKPOINT_EVERY:-20}"
CKPT_PATH="${CKPT_PATH:-state_iter.txt}"
LAUNCH_MODE="${LAUNCH_MODE:-direct}"
MAX_ITER="${MAX_ITER:-500}"
MODULE_LIST="${MODULE_LIST:-anaconda3/2023.07}"
RUNNER_MARGIN_SEC="${RUNNER_MARGIN_SEC:-60}"
RUNNER_TIME_LIMIT="${RUNNER_TIME_LIMIT:-00:03:00}"
SRUN_ARGS="${SRUN_ARGS:--n 1}"
###############################################################################
# Slurm directives (keep RUNNER_TIME_LIMIT <= 24 hours)
###############################################################################
#SBATCH --job-name=ckpt_runner_demo
#SBATCH --output=log_runner_%j.out
#SBATCH --error=log_runner_%j.err
#SBATCH --time=00:03:00
#SBATCH --ntasks=1
#SBATCH --cpus-per-task=1
#SBATCH --mem=512M
#SBATCH --partition=centos7
#SBATCH --qos=normal
###############################################################################
# Exit on error
###############################################################################
set -euo pipefail
###############################################################################
# Helpers
###############################################################################
shopt -s expand_aliases
alias dtstamp="date +%Y%m%d-%H:%M:%S"
info(){ echo "Info[$(dtstamp)]: $*"; }
get_ckpt_iter() {
  [[ -f "${CKPT_PATH}" ]] || { echo 0; return; }
  tr -cd '0-9' < "${CKPT_PATH}" 2>/dev/null || echo 0
}
to_seconds() {
        # Acceptable time formats include "minutes", "minutes:seconds", "hours:min- utes:seconds",
        # "days-hours", "days-hours:minutes" and "days-hours:minutes:seconds"
        local input="$1"
        # Handle days-hours format by replacing '-' with ':' to unify the delimiter
        # Then split components into an array
        IFS=':' read -r -a parts <<< "${input//-/:}"
        case ${#parts[@]} in
            1) # Format: minutes
                seconds=$((parts[0] * 60))
                ;;
            2) # Formats: minutes:seconds OR days-hours
                if [[ $input == *"-"* ]]; then
                    seconds=$((parts[0] * 86400 + parts[1] * 3600))
                else
                    seconds=$((parts[0] * 60 + parts[1]))
                fi
                ;;
            3) # Formats: hours:minutes:seconds OR days-hours:minutes
                if [[ $input == *"-"* ]]; then
                    seconds=$((parts[0] * 86400 + parts[1] * 3600 + parts[2] * 60))
                else
                    seconds=$((parts[0] * 3600 + parts[1] * 60 + parts[2]))
                fi
                ;;
            4) # Format: days-hours:minutes:seconds
                seconds=$((parts[0] * 86400 + parts[1] * 3600 + parts[2] * 60 + parts[3]))
                ;;
            *)
                echo "Unsupported format"
                exit 1
                ;;
        esac
        echo "$seconds"
}
###############################################################################
# Log settings
###############################################################################
info "Start on $(hostname); JOBID=${SLURM_JOB_ID:-unknown}"
info "Runner settings:"
info "APP_CMD=${APP_CMD}"
info "CHECKPOINT_EVERY=${CHECKPOINT_EVERY}"
info "CKPT_PATH=${CKPT_PATH}"
info "LAUNCH_MODE=${LAUNCH_MODE}"
info "MAX_ITER=${MAX_ITER}"
info "MODULE_LIST=${MODULE_LIST}"
info "RUNNER_MARGIN_SEC=${RUNNER_MARGIN_SEC}"
info "RUNNER_TIME_LIMIT=${RUNNER_TIME_LIMIT}"
info "SRUN_ARGS=${SRUN_ARGS}"
###############################################################################
# Load requested modules
###############################################################################
info "Loading modules."
module load "${MODULE_LIST}"
###############################################################################
# Timeout window
###############################################################################
TOTAL_SEC=$(to_seconds "${RUNNER_TIME_LIMIT}")
RUN_WINDOW_SEC=$(( TOTAL_SEC - RUNNER_MARGIN_SEC ))
if (( RUN_WINDOW_SEC <= 0 )); then
  info "WARNING: RUN_WINDOW_SEC <= 0; using 1s."
  RUN_WINDOW_SEC=1
fi
before_iter=$(get_ckpt_iter)
set +e
if [[ "${LAUNCH_MODE}" == "srun" ]]; then
  # timeout -> srun -> bash -lc "APP_CMD"
  # On expiry, timeout sends TERM to srun; srun forwards signals to its job step tasks.
  timeout "${RUN_WINDOW_SEC}s" srun ${SRUN_ARGS} bash -lc "${APP_CMD}"
else
  # direct mode: run in the batch shell
  timeout "${RUN_WINDOW_SEC}s" bash -lc "${APP_CMD}"
fi
rc=$?
set -e
info "Program exit code (from timeout wrapper): ${rc}"
###############################################################################
# Interpret exit-code from timeout
#   0   = completed all iterations (no further submissions necessary)
#   99  = app voluntarily checkpointed early -> submitter should continue
#   124 = timeout before walltime expiry -> checkpoint likely written -> continue
###############################################################################
if [[ ${rc} -eq 0 ]]; then
  info "Application finished all iterations."
  exit 0
elif [[ ${rc} -eq 99 ]]; then
  info "Application exited after writing checkpoint."
  exit 99
elif [[ ${rc} -eq 124 ]]; then
  after_iter=$(get_ckpt_iter)
  if (( after_iter > before_iter )); then
    info "Timeout + checkpoint advance detected (${before_iter}->${after_iter})."
    exit 124
  else
    info "Timeout but checkpoint did not advance. Marking failure."
    exit 1
  fi
else
  info "Unexpected exit code: ${rc}"
  exit "${rc}"
fi

Post-workflow analysis in Python

Plotting execution time and memory usage

Once the last in the series of checkpoint_submitter.sh jobs has detected the end of the computational workflow, it will call on the Python scripts listed below to perform a post-worflow analysis in order to plot execution time and memory usage (see output fields Elapsed and MaxRSS in man sacct) and identify possible anomalies from among all of the checkpoint_runner jobs that have participated in the workflow.

The types of anomalies determined, if any are the following.

  • | Z | > 3.5 for single job execution time (Elapsed in the above), where
Z = (value - mean) / (standard deviation)
  • modZ > 3.5 for maximum memory usage by a single job (MaxRSS in the above), where
modZ = 0.6745 * | value - median | / (Median Absolute Deviation)

See also NIST - Detection of Outliers.

Python scripts

Here are two Python scripts used by the checkpoint submitter to analyze and plot usage and annotate anomalies in execution time and memory usage by the checkpoint runner jobs.

Aggregate usage

Here is the listing for the file aggregate_usage.py used in checkpoint_submitter.sh.

aggregate_usage.py
#!/usr/bin/env python3
"""
aggregate_usage.py  (SLURM 14.x–compatible)
-------------------------------------------------------------
Combines parent and .batch accounting rows so MaxRSS is preserved.

SLURM 14.x specifics:
  - Only .batch steps contain correct MaxRSS
  - Parent jobs often have empty MaxRSS
  - ElapsedRaw is not available
  - Elapsed may be MM, MM:SS, HH:MM:SS, D-HH, D-HH:MM, D-HH:MM:SS

Outputs worker_usage.csv:
  JobID, ElapsedSeconds, TotalCPU, MaxRSS_bytes, MaxRSS_MiB,
  ReqMem, NodeList, State
"""

import subprocess
import pandas as pd
import sys
import re
from io import StringIO

IDFILE = "worker_ids.txt"
OUTFILE = "worker_usage.csv"


# ---------------------------------------------------------
# Utilities
# ---------------------------------------------------------
def run_cmd(cmd):
    return subprocess.check_output(cmd, shell=True, text=True)


def parse_elapsed_to_seconds(elapsed):
    if not isinstance(elapsed, str):
        return None

    s = elapsed.strip()
    days = 0

    # Day prefix
    if "-" in s:
        d, rest = s.split("-", 1)
        try:
            days = int(d)
        except:
            return None
    else:
        rest = s

    parts = rest.split(":")

    if len(parts) == 1:      # MM or D-HH
        try:
            x = int(parts[0])
        except:
            return None
        if days > 0:
            hours, minutes, seconds = x, 0, 0
        else:
            hours, minutes, seconds = 0, x, 0

    elif len(parts) == 2:    # MM:SS or D-HH:MM
        try:
            a = int(parts[0])
            b = int(parts[1])
        except:
            return None
        if days > 0:
            hours, minutes, seconds = a, b, 0
        else:
            hours, minutes, seconds = 0, a, b

    elif len(parts) == 3:    # HH:MM:SS or D-HH:MM:SS
        try:
            hours = int(parts[0])
            minutes = int(parts[1])
            seconds = int(parts[2])
        except:
            return None
    else:
        return None

    return days*86400 + hours*3600 + minutes*60 + seconds


def parse_rss_to_bytes(val):
    if val is None or pd.isna(val):
        return None
    s = str(val).strip().rstrip("nN")
    try:
        if s.endswith(("K","k")):
            return float(s[:-1]) * 1e3
        if s.endswith(("M","m")):
            return float(s[:-1]) * 1e6
        if s.endswith(("G","g")):
            return float(s[:-1]) * 1e9
        if re.fullmatch(r"\d+(\.\d+)?", s):
            return float(s)
    except:
        return None
    return None


# ---------------------------------------------------------
# Main
# ---------------------------------------------------------
def main():

    try:
        with open(IDFILE) as f:
            jobids = [x.strip() for x in f if x.strip()]
    except:
        print(f"ERROR: {IDFILE} not found.")
        sys.exit(1)

    if not jobids:
        print("No job IDs to process.")
        sys.exit(0)

    fields = [
        "JobID", "Elapsed", "TotalCPU", "MaxRSS",
        "ReqMem", "NodeList", "State"
    ]

    cmd = f"sacct -j {','.join(jobids)} --format={','.join(fields)} -P"
    raw = run_cmd(cmd)

    df = pd.read_csv(StringIO(raw), sep="|")
    df.dropna(how="all", inplace=True)

    # Split BaseID with explicit keywords (older pandas compatibility)
    df["BaseID"] = (
        df["JobID"].astype(str)
        .str.split(pat=".", n=1, regex=False)
        .str[0]
    )

    df["IsBatch"] = df["JobID"].astype(str).str.endswith(".batch")

    parent = df[~df["IsBatch"]].copy()
    batch  = df[df["IsBatch"]].copy()

    merged = pd.merge(
        parent,
        batch[["BaseID","MaxRSS"]],
        on="BaseID",
        how="left",
        suffixes=("", "_batch")
    )

    def choose(x):
        if pd.notna(x["MaxRSS"]):
            return x["MaxRSS"]
        return x["MaxRSS_batch"]

    merged["MaxRSS"] = merged.apply(choose, axis=1)

    merged["MaxRSS_bytes"] = merged["MaxRSS"].apply(parse_rss_to_bytes)
    merged["MaxRSS_MiB"] = merged["MaxRSS_bytes"] / (1024.0**2)

    merged["ElapsedSeconds"] = merged["Elapsed"].apply(parse_elapsed_to_seconds)

    out = merged[[
        "BaseID","ElapsedSeconds","TotalCPU","MaxRSS","MaxRSS_bytes",
        "MaxRSS_MiB","ReqMem","NodeList","State"
    ]].rename(columns={"BaseID": "JobID"})

    out.to_csv(OUTFILE, index=False)
    print(f"Wrote {OUTFILE}")
    print(out.head())


if __name__ == "__main__":
    main()

Plot progress

Here is the listing for the file plot_progress.py used in checkpoint_submitter.sh for generating .png plot files for run time and memory usage by the checkpoint runner jobs.

plot_progress.py
#!/usr/bin/env python3
"""
plot_progress.py

Produces:
  - progress_with_anomalies.png     (dual-axis: checkpoints + MaxRSS MiB)
  - resource_trend.png              (dual-axis: ElapsedSeconds + MaxRSS MiB)
  - anomaly_details.csv             (per-job anomalies)
  - anomaly_stats_table.png         (summary table)
"""

import pandas as pd
import matplotlib.pyplot as plt
import datetime as dt
import numpy as np
import glob
import re
import os

USAGE_FILE = "worker_usage.csv"
LOG_GLOB   = "log_runner_*.out"


# ---------------------------------------------------------
# Utilities
# ---------------------------------------------------------
def parse_worker_logs():
    rows = []
    for fp in glob.glob(LOG_GLOB):
        m = re.search(r"log_runner_(\d+)\.out", os.path.basename(fp))
        if not m: continue
        jid = int(m.group(1))

        with open(fp, "r", errors="ignore") as f:
            for line in f:
                if "Info[" in line:
                    try:
                        ts = line.split("Info[")[1].split("]")[0]
                        t  = dt.datetime.strptime(ts,"%Y%m%d-%H:%M:%S")
                        rows.append((jid,t))
                        break
                    except:
                        pass
    return pd.DataFrame(rows, columns=["JobID","StartTime"]) if rows else \
           pd.DataFrame(columns=["JobID","StartTime"])


def numeric_jobid(s):
    m = re.match(r"^(\d+)", str(s))
    return int(m.group(1)) if m else None


def time_anomalies(elapsed):
    s = elapsed.astype(float)
    if s.std(ddof=0)==0:
        return pd.Series(False,index=s.index), pd.Series(0.0,index=s.index)
    z = (s-s.mean())/s.std(ddof=0)
    return (z.abs()>3.5), z


def mem_anomalies(mem_mib, window=10, thresh=3.5):
    s = mem_mib.astype(float)
    med = s.rolling(window,min_periods=3).median()
    absd = (s-med).abs()
    mad  = absd.rolling(window,min_periods=3).median()
    modz = 0.6745 * absd / mad.replace(0,np.nan)
    modz = modz.fillna(0)
    return (modz>thresh), modz


def save_summary(summary, details, fname="anomaly_stats_table.png"):
    fig, ax = plt.subplots(figsize=(11,6))
    ax.axis("off")

    rows = [[k,str(v)] for k,v in summary.items()]
    stab = ax.table(
        cellText=rows,
        colLabels=["Metric","Value"],
        bbox=[0,0.55,0.45,0.4]
    )
    stab.auto_set_font_size(False)
    stab.set_fontsize(11)

    anom = details[details["AnomalyType"]!="none"]
    if len(anom)>12: anom = anom.head(12)
    if not anom.empty:
        atab = ax.table(
            cellText=anom.astype(str).values,
            colLabels=list(anom.columns),
            bbox=[0,0.05,1,0.45]
        )
        atab.auto_set_font_size(False)
        atab.set_fontsize(9)

    fig.tight_layout()
    fig.savefig(fname,dpi=150)
    plt.close(fig)
    print(f"Saved {fname}")


# ---------------------------------------------------------
# Main
# ---------------------------------------------------------
def main():

    df = pd.read_csv(USAGE_FILE)
    df = df[df["ElapsedSeconds"].notnull()].reset_index(drop=True)

    if "MaxRSS_MiB" not in df.columns:
        print("ERROR: worker_usage.csv missing MaxRSS_MiB.")
        return

    df["JobID"] = df["JobID"].apply(numeric_jobid)
    df = df[df["JobID"].notnull()].reset_index(drop=True)

    logs = parse_worker_logs()
    merged = pd.merge(df, logs, on="JobID", how="inner")

    if merged.empty:
        print("ERROR: No matching logs.")
        return

    merged = merged.sort_values("StartTime").reset_index(drop=True)

    times   = merged["StartTime"].tolist()
    idxs    = np.arange(len(merged))
    elapsed = merged["ElapsedSeconds"].astype(float)
    mem_mib = merged["MaxRSS_MiB"].astype(float)

    # Detect anomalies
    mtime, ztime = time_anomalies(elapsed)
    mmem,  zmem  = mem_anomalies(mem_mib)

    both  = mtime & mmem
    tonly = mtime & ~mmem
    monly = mmem  & ~mtime

    # -----------------------------------------------------
    # 1. progress_with_anomalies.png
    # -----------------------------------------------------
    fig, ax1 = plt.subplots(figsize=(12,6))

    # Checkpoint curve with dots
    ax1.plot(times, idxs, 'o-', color="gray", label="Checkpoint Progress")
    ax1.set_xlabel("Wall Time")
    ax1.set_ylabel("Checkpoint Number",color="gray")

    # Anomaly markers
    for i,t in enumerate(times):
        if both[i]:
            ax1.plot(t, idxs[i], 'o', color="purple", markersize=10,
                     label="Both anomalies" if i==0 else "")
        elif tonly[i]:
            ax1.plot(t, idxs[i], 'o', color="orange", markersize=9,
                     label="Time anomaly" if i==0 else "")
        elif monly[i]:
            ax1.plot(t, idxs[i], 'o', color="blue", markersize=9,
                     label="Memory anomaly" if i==0 else "")

    # MaxRSS dual-axis with dots
    ax2 = ax1.twinx()
    ax2.plot(times, mem_mib.values, 'bo-', markersize=5,
             alpha=0.70, label="MaxRSS (MiB)")
    ax2.set_ylabel("MaxRSS (MiB)", color="blue")

    # Highlight memory anomalies on memory curve
    for i,t in enumerate(times):
        if monly[i]:
            ax2.plot(t, mem_mib.values[i], 'bo', markersize=8)
        elif both[i]:
            ax2.plot(t, mem_mib.values[i], 'mo', markersize=10)

    h1,l1 = ax1.get_legend_handles_labels()
    h2,l2 = ax2.get_legend_handles_labels()
    ax1.legend(h1+h2, l1+l2, loc="upper left")

    fig.tight_layout()
    fig.savefig("progress_with_anomalies.png")
    plt.close(fig)
    print("Saved progress_with_anomalies.png")

    # -----------------------------------------------------
    # 2. resource_trend.png  (Elapsed vs MaxRSS dual-axis)
    # -----------------------------------------------------
    fig2, axL = plt.subplots(figsize=(12,6))

    axL.plot(elapsed.values, 'ko-', markersize=5,
             label="Elapsed (sec)")
    axL.set_xlabel("Worker Job Index (time-ordered)")
    axL.set_ylabel("Elapsed Seconds",color="black")

    axR = axL.twinx()
    axR.plot(mem_mib.values, 'bo-', markersize=5,
             alpha=0.7, label="MaxRSS (MiB)")
    axR.set_ylabel("MaxRSS (MiB)",color="blue")

    hL,lL = axL.get_legend_handles_labels()
    hR,lR = axR.get_legend_handles_labels()
    axL.legend(hL+hR, lL+lR, loc="upper left")

    fig2.tight_layout()
    fig2.savefig("resource_trend.png")
    plt.close(fig2)
    print("Saved resource_trend.png")

    # -----------------------------------------------------
    # 3. anomaly_details + summary table
    # -----------------------------------------------------
    details = pd.DataFrame({
        "JobID": merged["JobID"],
        "StartTime": merged["StartTime"],
        "ElapsedSeconds": elapsed,
        "MaxRSS_MiB": mem_mib,
        "TimeZ": ztime,
        "MemModZ": zmem
    })

    atype = np.where(both, "both",
             np.where(tonly, "time",
             np.where(monly,"memory","none")))
    details["AnomalyType"] = atype

    summary = {
        "Total jobs": len(details),
        "Anomalies": int((atype!="none").sum()),
        "Time only": int((atype=="time").sum()),
        "Memory only": int((atype=="memory").sum()),
        "Both": int((atype=="both").sum())
    }

    details.to_csv("anomaly_details.csv", index=False)
    print("Saved anomaly_details.csv")

    save_summary(summary, details)


if __name__ == "__main__":
    main()

Working Examples

Common features among the examples

Each of the example application scripts included here are designed for use with the pair of job scripts.checkpoint_submitter.sh and checkpoint_runner.sh

As part of that design, each of the application scripts implements the following list of features or capabilities in its own specific language.

  1. Each application script handles the SIGTERM signal sent by the Checkpoint Runner job immediately before that job times out.
  2. Each application script performs its own periodic checkpointing or saving intermediate or partial results, periodically.
  3. Each application script resumes from the most recently saved checkpoint, if any, when invoked by the Checkpoint Runner.
  4. Each application script uses the following settings in the form of BASH environment variables (see Environment Variables) with default values that can be overridden beforehand or at time of submittal of the checkpoint_submitter.sh job script. (See Overriding default settings.)
    • CKPT_PATH - file path of checkpoint value (default varies)
    • CHECKPOINT_EVERY - number of loop iterations between periodic checkpoints (defaults to 20)
    • MAX_ITER - maximum number of loop iterations to perform (defaults to 500)

Make copies of the BASH and Python scripts

To use any of the checkpointing examples mentioned below, you'll need to make your own copies of the required BASH and Python scripts in your own environment on Cypress.

Make copies of the BASH scripts checkpoint_submitter.sh and checkpoint_runner.sh

All of the examples linked further below make use of the following two (2) BASH job scripts mentioned above.

Make copies of the Python scripts aggregate_usage.py and plot_progress.py

Also, the checkpoint_submitter.sh script calls out the following two (2) Python scripts for post-workflow analysis of execution time and memory usage by the checkpoint runner jobs.

BASH Checkpointing Example

See BASH Checkpointing Example

Python Checkpointing Example

See Python Checkpointing Example

R Checkpointing Example

See R Checkpointing Example

MATLAB Checkpointing Example

See MATLAB Checkpointing Example

Note: See TracWiki for help on using the wiki.