Indexer hangs (deadlock) and blows up RAM on a mid-size MQL5 codebase #775

Version

v0.8.1

Platform

Windows (x64)

Install channel

GitHub release archive / install.sh / install.ps1

Binary variant

standard

What happened, and what did you expect?

Title

Indexer hangs (deadlock) and blows up RAM on a mid-size MQL5 codebase (v0.8.1)

Summary

Indexing a MetaTrader 5 MQL5 project never finishes. Two failure modes, both fatal:

1. RAM blowup during parallel extraction (up to ~62 GB on a 64 GB machine — once it filled RAM and crashed the whole PC).
2. Deadlock — the run freezes partway (~22–26 of 112 files), no more log output, no progress, the graph phase is never reached.

Version

• codebase-memory-mcp 0.8.1 (confirmed the latest release on GitHub).

Environment

• Windows 10, 64 GB RAM, 24 logical CPUs.
• Run via CLI: codebase-memory-mcp cli index_repository '{"repo_path":"...","mode":"fast"}'.

What the project is (language)

• MQL5 = MetaQuotes Language 5, the language for MetaTrader 5 trading robots. It is syntactically very close to C++ (classes, OOP, #include, etc.).
• Files: .mq5 (main programs) and .mqh (headers).
• Since there is no native MQL5 parser, they are mapped to the C++ extractor in .codebase-memory.json:
  {"extra_extensions": {".mq5": "cpp", ".mqh": "cpp"}}
• Size: ~112 files, ~48,000 lines total. Largest file ~5,200 lines. Heavy cross-#include structure (many files include a big central header).

Steps to reproduce

1. Point the indexer at a large MQL5 (or generally C++-heavy, deeply cross-included) repo with the .mq5/.mqh → cpp mapping.
2. index_repository with mode: fast.
3. Watch RAM and the log.

Observations

• Log shows pipeline.mode mode=parallel workers=24 (= number of logical CPUs) and parallel.mem.budget total_mb=32458 — but actual RAM goes to 42–62 GB, so the budget is not enforced.
• With the cpp mapping, a few specific files take 10–12 minutes each to "extract". Example: a 392-line file (Gold_SSI_TSI_SIGNAL.mqh) took 726,345 ms — its only #include pulls a 5,229-line header. DrawOrderFunc.mqh took 597,887 ms. This looked like an O(n²)-style symbol-resolution blowup, made much worse by duplicate class definitions across backup/old copies of files (removing those duplicates dropped that same header to 103 ms).
• After cleaning duplicates and fixing 2 circular includes, RAM stayed lower (~35–45 GB) but the run still deadlocked around file 22–26.
• Switching the mapping to {".mq5":"c",".mqh":"c"} made per-file extraction fast again (2.5 s max, RAM ~22 GB) — but it STILL deadlocked at the same point (22/112), frozen for 16+ minutes on the same 4 files:
  Defines_generalFunc.mqh, DrawOrderFunc.mqh, DrawRectangleSR.mqh, PositionsManagment.mqh.
  (These files show parallel.extract.file.start with no matching parallel.extract.file.done, memory flat, no new log lines.)
• Conclusion: the deadlock is independent of the language mapping (cpp vs c), of memory, and of the file cleanup. It looks like a worker-pool / parallel-extraction deadlock in the tool itself.

Things I tried that did NOT help

• GOMAXPROCS=2 → ignored, still workers=24.
• Limiting the process CPU affinity to 4 cores → ignored, still workers=24.
• mode: fast, delete_project + fresh reindex, killing all other codebase-memory processes first.
• There is no config option for worker count / concurrency, and no exclude/ignore option (config list only exposes auto_index and auto_index_limit); .gitignore is not honored for source dirs.

Also worth noting

• auto_index = true re-triggered the RAM blowup automatically every time the MCP server reconnected. Setting auto_index = false was needed to stop it.

Feature requests / suggested fixes

1. A --workers / concurrency cap (config or flag) so peak RAM is bounded on large files.
2. Actually enforce mem_budget during parallel extraction.
3. An exclude/ignore option (or honor .gitignore) to skip specific files/dirs.
4. Investigate the deadlock in parallel extraction — it reproduces on the 4 files above regardless of cpp/c mapping.

Reproduction

1. Code being indexed: a private MQL5 (MetaTrader 5) trading codebase — can't share publicly.
   Structure that triggers it: ~112 .mq5/.mqh files mapped to cpp, with heavy cross-#includes
   and one central ~5,200-line header (ManagmentClass.mqh) that many files pull in.
   Minimal pattern that seems to matter:

// ManagmentClass.mqh — ~5,200 lines, many classes
// Gold_SSI_TSI_SIGNAL.mqh (392 lines): #include "..\trading\ManagmentClass.mqh"
// DrawOrderFunc.mqh: includes 6 other module headers (Defines, sync, DB, history, ...)

.codebase-memory.json: {"extra_extensions": {".mq5": "cpp", ".mqh": "cpp"}}

2. Command:
   codebase-memory-mcp cli index_repository '{"repo_path":"C:/.../MQL5/Experts/BM","mode":"fast"}'

3. Result vs Expected:

• RESULT: extraction runs to ~22 of 112 files, then freezes forever — no more
  parallel.extract.file.done, never reaches a graph/persist phase, RAM flat (~22 GB with the
  c mapping) or climbing to 42–62 GB (with the cpp mapping), no new log lines for 15–40 min.
  The same 4 files are stuck (started, never finished): Defines_generalFunc.mqh,
  DrawOrderFunc.mqh, DrawRectangleSR.mqh, PositionsManagment.mqh.
• EXPECTED: indexing completes and writes the graph — as it does in seconds for my 3 other repos
  (NestJS backend, two Next.js frontends).

Note: I can privately share those 4 .mqh files if that helps you reproduce — a public minimal
repro isn't available since the code is proprietary.

Logs

Diagnostics trajectory (memory / performance / leak issues)

Project scale (if relevant)

~112 files, ~40,000 lines (MQL5). Indexing never completes (deadlocks ~22/112), so no final node/edge count.

Confirmations

• I searched existing issues and this is not a duplicate.
• My reproduction uses shareable code (a dummy snippet or a public OSS repository), not proprietary code.