An Insight into the Advanced XIP Filesystem (AXFS)

on YouTube ↗35m

" summary

AXFS implements page-granular XIP plus per-page compression and uses an in‑kernel profiling pass that logs which pages become executable, feeding an image builder that marks those pages XIP. Images can do device spanning so NOR holds XIP pages and NAND holds compressed pages. A simple instrumentation tool emits a linker-script locality tool that clusters hot functions. On an ARMv6 board with a 500‑function synthetic workload (~1.6 KB each) XIP images show the fastest launch and smallest RAM footprint, compressed images show the smallest on‑flash size.

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" chapters (28)

1. 0:00Introduction
2. 0:30Background
3. 1:10Embedded Systems
4. 2:31Overview
5. 3:49XIP Diagram
6. 4:32Advantages
7. 5:25Disadvantages
8. 7:31Device Spanning
9. 8:58XIP Profiling
10. 11:15AXFS By Tables
11. 12:57Code Snippet
12. 14:02Format
13. 15:33Regions
14. 17:23Superblock Structure
15. 17:37Regions XFS Images
16. 18:41Node Index Region
17. 20:57C Block
18. 22:24Index
19. 22:45AXFS Performance
20. 23:35AXFS Performance Parameters
21. 24:17Improving Code Locality
22. 25:17Improving Page Faults
23. 27:07XFS Performance
24. 28:16Timing Measurement
25. 31:06Total Size Measurement
26. 32:32System Ram Footprint
27. 33:54XFS RAM Footprint
28. 34:22AXFS Key Points

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