[perf-scan] 2026-08-21 -- performance opportunities found

[github-actions]

Performance Scan - 2026-08-21

Automated scan of src/apm_cli/ for algorithmic performance anti-patterns.
2 finding(s) identified.

Findings

[C] Unconditional Expensive Operation -- src/apm_cli/compilation/context_optimizer.py:874-875

• Current: O(F x P) filesystem syscalls -- file_path.resolve() and
  self.base_dir.resolve() are called inside _file_matches_pattern for
  every (file, **-pattern) pair. self.base_dir is already a resolved path
  (set at construction, line 144), so self.base_dir.resolve() is a redundant
  syscall on every call. file_path.resolve() repeats for every file that
  reaches the ** branch, even though file paths are constructed once during
  _analyze_project_structure.
• Proposed: O(1) base-dir resolve (use self.base_dir directly) + O(F) total
  file-path resolves (pre-compute once during _analyze_project_structure).
• Fix: Store resolved file paths in _files_by_directory during
  _analyze_project_structure and replace self.base_dir.resolve() with
  self.base_dir at line 875; _file_matches_pattern then needs no syscalls
  on the ** branch.

[C] Unconditional Expensive Operation -- src/apm_cli/compilation/context_optimizer.py:1406

• Current: O(D x depth x I) Path.resolve() syscalls -- _is_instruction_relevant
  calls working_directory.resolve() (line 1406) for every non-global instruction.
  Its sole caller, analyze_context_inheritance, passes the same working_directory
  for all inner-loop iterations (lines 341-349), so the resolve is repeated
  O(depth x I) times per directory, and _calculate_optimization_stats calls
  analyze_context_inheritance for every directory D in the project, giving
  O(D x depth x I) redundant resolves during the stats phase.
• Proposed: O(D) resolve() calls total for the stats pass.
• Fix: Compute resolved_working_dir = working_directory.resolve() once at the
  top of analyze_context_inheritance and pass the pre-resolved path into
  _is_instruction_relevant (add a resolved_working_dir parameter or hoist
  the resolve into the caller).

Scan coverage

• src/apm_cli/ (430 files scanned)
• Patterns checked: A (quadratic loops), B (linear scan in loop),
  C (unconditional expensive ops), D (redundant config parsing),
  E (heavy top-level imports), F (sequential independent I/O)

Generated by Daily Performance Scanner · 133 AIC · ⌖ 6.3 AIC · ⊞ 7.3K · ◷

• expires on Aug 28, 2026, 1:46 AM UTC