Notes

User preferences

Wants concise, codebase-grounded lessons
Learning style: applied, code-first (wants to see the concepts in their own assembly code)
Topic request was: "about realmode and protectmode" → "figure out cons and pos" → "continue"
- "cons and pos" interpreted as "concepts and positions" — the conceptual understanding of each mode and how they position relative to each other in the boot flow

Lesson 1: Real Mode — segment:offset, 1 MB limit, BIOS interrupts, prot_to_real/vesa2_detect
Lesson 2: TCB — Ring 0/3 boundary, JCore TCB map, boot chain of trust
Lesson 3: MMU — 32-bit page tables, TLB, page faults, CR0.PG, JCore's page fault handler
Lesson 4: Long Mode — 64-bit vs 32-bit, 4-level paging, canonical addresses, EFER.LME
Lesson 5: Disable Paging — identity mapping, triple fault, long→compat mode drop
Lesson 6: Boot Stages — GRUB→crt0.S→multiboot_main→main→start_domain_zero→Init domain
Lesson 7: jxmalloc — kernel bitmap allocator, 1024-byte blocks, two-tier with bump allocator per-domain

Ask user: GDT layout (segments.h, asm.S GDT entries), boot process deep dive (crt0.S), or JCore-specific portal/domain isolation pattern?

Lesson 9: GC I — reachability model. "Garbage = unreachable from roots." Grounded in gc_org.c:1084 root scanning + malloc_code bump allocator. Quiz widget built (assets/quiz.js).
Lesson 10: Scheduler — two-level round-robin runqueue (runq.c), switch.S context switch, idle+hlt, LLS/HLS Java-scheduler split, GC interface (Sched_gc_rootSet, gc_org_moveSchedulerObject).
Reference: reference/gc-glossary.html, reference/scheduler.html.

Safepoints: how JCore stops mutators so the GC can run (bridges scheduler → GC mission).
Then the promised GC II: copying/semispace collector — walk gc_org_gc() end to end (from/to space, forwarding pointers, bump allocation).
Generational heap (Eden/Survivor/Old), mark-compact (gc_compacting.c), G1/ZGC.