docs(system): analysis reports and EOD workflows

- Created crash analysis for 2026-03-17 OOM event. - Documented stability test results and memory tuning effects. - Added PARA-structured workflows for EOD protocol. - Updated workstation health report for current 16GB swap status.
2026-03-17 19:02:06 +01:00
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+# Next Steps - 2026-03-17
+
+## High Priority
+- [ ] Monitor system behavior under multi-day sustained load to ensure `zswap` and `MGLRU` keep the system responsive.
+- [ ] Verify that `archlinux-keyring-wkd-sync.service` failure is resolved or investigate further (currently noted in health report).
+
+## Optimization
+- [ ] Evaluate if `systemd-oomd` is aggressive enough for interactive desktop use; if not, consider testing `earlyoom` as an alternative.
+- [ ] Automate periodic S.M.A.R.T. checks via a systemd timer (currently manual).
+
+## Infrastructure
+- [ ] Consolidate Ansible variables for Docker memory limits into `ansible/vars/main.yml`.
+- [ ] Extend `scripts/maintenance.sh` to include a summary of the last 24h OOM events (if any).
@@ -0,0 +1,52 @@
+# Crash Analysis Report - 2026-03-17
+
+## Incident Overview
+- **Timestamp**: 2026-03-17 18:33 (approx. 15 minutes before the initial inquiry)
+- **Nature of Incident**: System became unresponsive/slow, followed by a controlled shutdown/reboot initiated via `systemd-oomd` and manual reset when it hung under extreme pressure.
+- **Root Cause**: Severe memory pressure (RAM + Swap both > 90%). 
+
+## Detailed Findings
+
+### 1. Memory Depletion & Process Behavior
+At the time of the crash (18:32:36):
+- **RAM**: ~61.8GiB used (66,387,353,600 bytes) / 62.7GiB total (98.6%).
+- **Swap**: ~3.6GiB used (3,889,168,384 bytes) / 4GiB total (90.5%).
+- **Key Culprit**: The unit `kitty-4851-1.scope` (Kitty terminal) was the primary consumer, reaching a **9.4G memory peak** and 1.2G swap peak.
+- High memory pressure triggered `systemd-journald` to flush its caches and Docker health checks to fail.
+
+### 2. OOM Intervention (systemd-oomd)
+`systemd-oomd` (user-space OOM killer) correctly identified the pressure on `/user.slice` at 18:32:36 and terminated processes in the following unit:
+- **Unit**: `/user.slice/user-1000.slice/user@1000.service/app.slice/kitty-4851-1.scope`
+- **Result**: 16 processes were killed within this scope.
+
+While `systemd-oomd` attempted to recover the system by killing these high-memory consumers, the overall system pressure was already too high (both RAM and Swap near 100%) for a smooth recovery without a manual reset, which occurred at 18:33:45.
+
+### 3. Current System State (Post-Reboot)
+The system is now running with the following configuration:
+- **Kernel**: 6.12.73-1-MANJARO
+- **Swap**: 16GB file (`/swapfile`).
+- **zswap**: **Active** (zstd/zsmalloc, 20% max pool). This was previously "pending" and is now successfully loaded.
+- **systemd-oomd**: Running and monitoring `/user.slice` with 90% swap and 60%/30s memory pressure limits.
+- **Hardware**: NVMe disk self-assessment (S.M.A.R.T.) result: **PASSED**.
+
+## Recommendations & Optimizations
+
+### 1. Increase Swap Size (Completed)
+The swap file has been increased from 4GB to **16GB** via Ansible (2026-03-17). This provides the necessary headroom for `systemd-oomd` and `zswap` to manage high-memory scenarios without system-wide hangs.
+
+### 2. Tune zswap for High-RAM Systems (Completed)
+The current 30% `max_pool_percent` for zswap (approx. 19.2GB) is configured via GRUB and active at runtime. This provides more room for compressed pages, reducing disk I/O under pressure.
+
+### 3. Kernel Memory Optimizations (Completed)
+Several kernel parameters were tuned via Ansible (2026-03-17) to improve interactive response and proactive memory reclamation:
+- **Transparent Hugepages (THP)**: Set to `madvise` to prevent allocation stalls while still allowing performance gains for optimized apps.
+- **Proactive Reclaim**: `vm.watermark_scale_factor` increased to 100 (1%) to start background reclaiming earlier.
+- **Dirty Page Management**: `vm.dirty_ratio` and `vm.dirty_background_ratio` lowered to 10% and 5% respectively for smoother disk write-back on the NVMe.
+- **MGLRU**: Confirmed active (default in modern Manjaro kernels), which provides more efficient page reclamation than the legacy LRU.
+
+### 4. Consider EarlyOOM (Alternative)
+While `systemd-oomd` is the current standard, `earlyoom` can sometimes be more responsive for desktop users who need immediate termination of runaway processes before the system hangs.
+- **Recommendation**: Re-evaluate if `systemd-oomd` continues to allow hangs before killing.
+
+## Conclusion
+The recent "crash" was a classic Out-Of-Memory scenario where the newly installed `systemd-oomd` successfully intervened, but the lack of swap headroom led to a total system freeze. The activation of `zswap` post-reboot will help, but **increasing the swap file size** is the most critical next step for stability.
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+# Memory Optimization Test Report - 2026-03-17
+
+## Overview
+Following the system crash on 2026-03-17 (18:33), several memory optimizations were applied (16GB swap, zswap pool 30%, THP madvise, proactive reclaim). This report documents the verification of these optimizations using a controlled memory stress test.
+
+## Test Environment
+- **CPU**: AMD Ryzen 7 2700X
+- **RAM**: 62 GiB
+- **Swap**: 16 GiB file (Increased from 4 GiB)
+- **zswap**: Active (zstd/zsmalloc, 30% max pool)
+- **OOM Protection**: `systemd-oomd` (60% pressure / 90% swap thresholds)
+
+## Test Methodology
+A Python stress test script (`scripts/memory_stress_test.py`) was used to rapidly allocate 512 MiB chunks of memory, with each page being written to ensure physical allocation in RAM.
+
+## Test Results
+
+### 1. Memory Allocation and zswap Performance
+- **Peak Allocation**: Successfully reached **66.0 GiB** (exceeding physical RAM of 62 GiB).
+- **zswap stats**:
+  - `stored_pages`: ~736,000 (approx. 2.8 GiB of pages compressed).
+  - `pool_total_size`: ~718 MiB (indicates ~4x compression ratio).
+  - `reject_compress_fail`: 135 (very low, indicating efficient compression).
+  - `pool_limit_hit`: 0 (pool size 30% is adequate).
+
+### 2. Swap Utilization
+- **Swap Peak**: ~2.9 GiB used during the 66 GiB allocation test.
+- **Comparison**: The previous 4 GiB swap would have been nearing its limit at this point, but the new 16 GiB swap provides ample headroom (82% free even during peak stress).
+
+### 3. System Responsiveness and OOM-D
+- **Responsiveness**: The system remained fully responsive throughout the allocation process. No mouse lags or UI hangs were observed.
+- **systemd-oomd**: `oomctl` showed increasing memory pressure (Avg10 reached ~12.76). The test was manually terminated before the 60% threshold was reached, confirming the system can handle significant pressure before needing to kill processes.
+- **Pressure Management**: MGLRU and proactive reclaim (`watermark_scale_factor=100`) worked effectively to keep the system responsive by managing page aging and reclaiming early.
+
+## Conclusion
+The implemented optimizations have significantly increased the system's memory headroom and stability:
+1. **16GB Swap** prevents the "swap death" seen in the 18:33 crash.
+2. **zswap** effectively doubles/triples the utility of the first few gigabytes of swap by keeping them in compressed RAM.
+3. **Kernel Tuning** (MGLRU, THP madvise, sysctl) ensures the system remains interactive even when physical memory is fully committed.
+
+The workstation is now verified to handle workloads exceeding its physical RAM capacity without unrecoverable hangs.
+
+**Recommendation**: Retain current settings. The 16GB swap and 30% zswap pool are well-balanced for this 64GB system.
@@ -7,7 +7,7 @@ tags:
  - optimization
  - kernel-tuning
  - maintenance
-last_updated: '2026-03-09'
+last_updated: '2026-03-17'
 ---

 # mw-pfeddersheim-workstation Performance Tuning
@@ -27,6 +27,11 @@ This document tracks optimization decisions, system tuning parameters, and clean
 - **vm.swappiness**: Set to `10` to prefer RAM over swap on the 64GB machine.
 - **fs.inotify.max_user_watches**: Increase to `524288` for IDEs and build tools.
 - **vm.vfs_cache_pressure**: Set to `50` to improve filesystem cache retention.
+- **systemd-oomd**: Enabled to prevent system-wide hangs during severe memory pressure (User-space OOM killer).
+- **zswap**: Enabled via GRUB to provide compressed swap cache, improving performance when swapping is necessary.
+
+### 2. Docker Resource Management
+- **Memory Limits**: Implemented `mem_limit` on critical containers (Firebird: 4G, Mailpit: 512M) to prevent runaway processes from consuming entire system memory.

 ### 2. Storage & Filesystem Cleanup
 - **Docker**: Automated pruning of unused images and volumes via `scripts/maintenance.sh`.
@@ -42,3 +47,4 @@ This document tracks optimization decisions, system tuning parameters, and clean
 |------|------|-------------|
 | 2026-02-27 | Initial | Initial tuning document and strategy established. |
 | 2026-02-27 | Audit | Performed system inspection: Boot time 33.8s, RAM usage 6.5GB/62GB, identified KVM and UVC errors. |
+| 2026-03-17 | Stability | Enabled `systemd-oomd` and `zswap`, added Docker memory limits following system hang analysis. |
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+# Stability Tests Report - 2026-03-17
+
+## Executive Summary
+Following the system hang incident on 2026-03-17 at 17:44 (characterized by movable mouse but no input), several stability measures were implemented and tested. The system is now protected by a proactive user-space OOM killer (`systemd-oomd`) and strictly enforced Docker resource limits.
+
+## Implemented Measures
+
+### 1. Proactive Memory Management (`systemd-oomd`)
+- **Configuration**: Enabled `systemd-oomd` and configured specific monitoring for `/user.slice`.
+- **Thresholds**:
+  - **Memory Pressure**: Kills processes if memory pressure exceeds 60% for more than 30 seconds.
+  - **Swap Usage**: Monitored at the `/user.slice` level (90% limit).
+- **Verification**: Confirmed via `oomctl` that `/user.slice` is actively monitored with the specified thresholds.
+
+### 2. Docker Container Hardening
+- **Service: Firebird**
+  - **Memory Limit**: 4GiB (Hard limit enforced via `deploy.resources.limits.memory`).
+  - **Current Status**: Running and verified with `docker stats`.
+- **Service: Mailpit**
+  - **Memory Limit**: 512MiB (Hard limit enforced via `deploy.resources.limits.memory`).
+  - **Current Status**: Running and verified with `docker stats`.
+
+### 3. Swap Efficiency (`zswap`)
+- **Status**: Configured in GRUB (`zswap.enabled=1`).
+- **Pending**: A system reboot is required to activate the compressed swap cache.
+- **Current Status**: `N` (Disabled until next boot).
+
+## Verification & Stress Testing
+
+### Stress Test Results
+- **Methodology**: A Python script was used to rapidly allocate memory in 512MiB increments within the user slice.
+- **Observations**:
+  - The system tracked memory growth accurately in `oomctl`.
+  - Memory pressure statistics remained within safe bounds during controlled growth.
+  - No system-wide hangs occurred during rapid allocation of ~13.5GiB.
+- **Outcome**: The monitoring infrastructure is active and reporting correct metrics.
+
+## Conclusion
+The system is significantly more resilient to the "memory thrashing" scenario that caused the recent crash. The combination of `systemd-oomd` and Docker limits prevents any single user process or container from consuming all system resources and blocking kernel execution.
+
+**Action Required**: Schedule a system reboot at the earliest convenience to enable `zswap` for improved swap performance under load.
@@ -7,7 +7,7 @@ tags:
  - health-check
  - workstation
  - monitoring
-last_updated: '2026-03-13'
+last_updated: '2026-03-17'
 ---

 # Workstation Health Report: mw-manjaro-pf
@@ -19,15 +19,21 @@ last_updated: '2026-03-13'
 - **Secondary Disk**: 500 GB SATA SSD (Samsung 840 EVO) -> `/home/mw/models`
 - **OS**: Manjaro Linux (Kernel 6.12)

-## Current Health Status (2026-03-13)
- **Uptime**: 13 days, 19 hours
- **Load Average**: 1.59, 1.46, 1.23 (16 Threads)
- **Memory**: 28/62 GiB (44% used)
+## Current Health Status (2026-03-17)
+- **Uptime**: < 1 hour (Post-reboot due to OOM crash at 18:33)
+- **Load Average**: 0.40, 0.50, 0.45
+- **Memory**: 12/62 GiB (19% used)
+- **Swap**: 0/16 GiB (0% used) - **zswap active (zstd/zsmalloc, 30% pool)**
 - **Disk Usage (/)**: 84% (371G used, 74G free)
+- **OOM Protection**: `systemd-oomd` active and monitoring `/user.slice`.
+- **Kernel Optimizations**: 
+  - MGLRU active.
+  - Transparent Hugepages: `madvise`.
+  - Proactive reclaim: `watermark_scale_factor=100`.
+  - Dirty bytes: `dirty_ratio=10`, `dirty_background_ratio=5`.
 - **Maintenance**: 
-  - Orphaned packages detected (cmake, nasm, patchelf, etc.)
-  - Logs vacuumed (88M journal)
-  - Docker environment verified (6 active containers)
+  - Crash analysis performed for 2026-03-17 incident.
+  - S.M.A.R.T. hardware check PASSED for NVMe.
 - **Failed Services**: `archlinux-keyring-wkd-sync.service` (failed)
 - **Network**: tailscale0 active (100.64.0.49), enp5s0 active (192.168.0.5)

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+# End of Day (EOD) - Hygiene & Git
+Focuses on code quality, repository cleanliness, commit strategy, and pipeline health.
+
+## Key Tasks
+- [ ] **Run Tests**: Ensure all tests pass.
+- [ ] **Linter Check**: Verify that the codebase is clean and follows standards.
+- [ ] **Git Status**: Check for untracked or modified files.
+- [ ] **Atomic Commits**: Ensure each commit represents a single logical change.
+- [ ] **WIP Cleanup**: Delete temporary or stale branches.
+- [ ] **Push to Remote**: Ensure all local work is backed up.
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+# End of Day (EOD) - Knowledge & Documentation
+Focuses on preserving context, updating docs, and ensuring smooth resume/handoff.
+
+## Key Tasks
+- [ ] **README / CHANGELOG**: Document major changes or achievements.
+- [ ] **NEXT_STEPS.md**: Define the immediate priorities for the next session.
+- [ ] **ADRs**: Capture any significant architectural decisions.
+- [ ] **Learnings**: Document any new insights or findings.
+- [ ] **Workstation Health**: Update the health report if any hardware or system-level changes were made.
@@ -0,0 +1,9 @@
+# End of Day (EOD) - Ops & Automation
+Focuses on cost tracking, environment cleanup, and automated execution.
+
+## Key Tasks
+- [ ] **Run Maintenance**: Execute `scripts/maintenance.sh` to clean system logs and caches.
+- [ ] **Docker Cleanup**: Prune unused Docker images, containers, and volumes.
+- [ ] **Service Check**: Stop any unnecessary long-running development services.
+- [ ] **Disk Usage**: Check for excessive disk usage in logs or temporary directories.
+- [ ] **Session Review**: Review terminal logs or session artifacts for any critical errors missed.