Bulk Loop Guardian

A memory-safe wrapper for heavy iterations that monitors RAM usage and triggers an interactive failsafe if the environment approaches critical capacity.

Usage

loop_guardian(
  items,
  target_func,
  limit_mb = 4000,
  save_path = "emergency_checkpoint.rds"
)

Arguments

items

A vector or list of items to process.

target_func

The function to apply to each item.

limit_mb

Numeric. The memory limit in megabytes before triggering the alarm. Defaults to `4000`.

save_path

Character. Where to dump the emergency checkpoint data. Defaults to `"emergency_checkpoint.rds"`.

Value

A list of successfully processed results.

Details

The function provides a safeguard against memory-related crashes during large-scale batch processing:

1. Iterates through the `items` vector, applying `target_func` to each element.

2. Every 50 iterations, it checks the current memory usage using `gc()`.

3. If the memory usage exceeds `limit_mb`, it first attempts a deep garbage collection to recover RAM.

4. If memory remains above the threshold after GC, it triggers an interactive alarm, allowing the user to:

   • Save current progress to `save_path` and abort.

   • Ignore the limit and attempt to continue.

   • Abort immediately without saving.

Warning

This function modifies files on disk or the global environment. Please ensure you have a backup or are using version control (e.g., Git) before execution.

Examples

if (interactive()) {
  loop_guardian(items = 1:5, target_func = print)
}