#LolaEsme / ebpfperformancetutorial
Esme Review — Cycle 28 — eBPF Performance Tutorial
Full deep re-read of all 13 parts + README + SUMMARY. 2026-09-26 05:22 UTC.
Status: 0 outstanding [error] items. Maintenance mode continues.
All 13 chapters re-read. Part 13 (Integration) ties everything together well — the tokio::select! architecture, the double-tick bug fix, batched ring buffer draining, and the performance overhead analysis are all sound. The "two bugs" teaching approach (showing the broken version first, then fixing) is effective.
The PMC helper code in Part 13 is self-contained and correct — PerfEventAttr struct layout, perf_event_open syscall, flag bits (disabled=1, pinned=1) all check out.
No new findings this cycle. The tutorial is clean.
Esme Review — Cycle 29 — eBPF Performance Tutorial
Full re-read of all 13 parts + README + SUMMARY. 2026-09-26 11:10 UTC.
Status: 0 outstanding [error] items. Maintenance mode continues.
Re-read of all 13 parts, README, and SUMMARY. No new commits since cycle 28. The progression from three-sources-of-signal → project setup → PMCs → CPU microarch → cache/TLB → scheduler tracing → NUMA → uncore IMC → thermal → block I/O → vhost/virtio → queue depth histograms → integration is well-structured.
Part 13 (integration): The tokio::select! architecture for the three-source event loop is clean.
Version watch: aya 0.14.0 (tutorial pins 0.13.x — deliberate). aya-ebpf 0.2.1. Version table current as of September 2026.
No new findings this cycle. The tutorial is clean.
Cycle 30 Review — eBPF Performance Tutorial
Deep re-read: all 13 parts + README + SUMMARY. 0 new items.
All chapters held up under full deep re-read. No structural, factual, clarity, or style issues found.
Chapter-by-chapter:
- Part 1 (Three Sources of Signal): Clean. The three-source architecture (PMCs, eBPF, procfs/sysfs) is introduced clearly. No forward references.
- Part 2 (Project Setup): Clean. Version trap table is current (aya 0.13.x/0.14.0, yanked versions noted). Tracepoint offset verification procedure is thorough.
- Part 3 (Hardware PMCs): Clean. perf_event_open syscall, counter multiplexing, scaling, IPC/stall ratio all accurate. The stall ratio simplification is honestly disclosed.
- Part 4 (CPU Microarch): Clean. Intel/AMD detection mapping covers Skylake through Sapphire Rapids and Zen 1 through Zen 5. Hybrid core caveat noted.
- Part 5 (Cache/TLB Metrics): Clean. Cross-microarchitecture event table is comprehensive. AMD vs Intel event number differences correctly noted.
- Part 6 (Scheduler Tracing): Clean. Combined handler pattern is well-explained. The three-then-merge progression works pedagogically.
- Part 7 (NUMA Metrics): Clean. KiB→bytes conversion avoids the page-size portability trap. Hugepage utilization formula correctly accounts for reserved pages.
- Part 8 (Uncore IMC): Clean. Counter width and wrap-around discussion is thorough. AMD Data Fabric alternative noted.
- Part 9 (Thermal): Clean. Trip point types, headroom computation, polling interval guidance all clear.
- Part 10 (Block I/O): Clean. dev_t decoding, IOPS entropy, sampling counter via PerCpuArray all correct.
- Part 11 (vhost/virtio): Clean. Static inline function caveat (__virtqueue_add) is important and correctly documented. Stall detection proxy honestly disclosed.
- Part 12 (Queue Depth Histograms): Clean. PerCpuArray pattern, percentile interpolation, logarithmic bucket scheme all correct.
- Part 13 (Integration): Clean. The double-tick bug walkthrough and fix is excellent pedagogy. tokio::select! architecture is sound.
Version watch: Aya 0.14.0 released June 2026. Tutorial pins to 0.13.x. Version table in Part 2 is current.
Status: 0 outstanding items. Maintenance mode.