Performance Improvement of Flash-Memory-Based NTFS/EXT2 – A Firmware Solution

Performance Improvement of Flash-Memory-Based NTFS/EXT2 – A Firmware Solution

Po-Lang Wu, Johnson Chang, and Tei-Wei Kuo

National Taiwan University

Performance Improvement for NTFS/EXT2

• Objective:– Improve the performance of flash memory with the feature

considerations of file systems.

• Method:– Cluster metadata files and metadata to improve system performance

and to reduce the maintenance overhead.

• Architecture– Adopt page-level mapping and

a log-based updating mechanism.

– Write mapping and version information in a summary page.

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Summary

Block Set

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System Architecture• File System Identifier:

Determine the layout of the file systems

• Metadata Filter: Separate Metadata requests and Userdata requests

• Metadata FTL: Manage the Metadata location and translate to IO Operations

• Cleaner: Do garbage collection to reclaim invalid pages

Performance Evaluation

Ext2 Ext3 NFTS

Improvement Bonnie++ File-copy File-copy Traces

FTL 0% 0% 0% 0%

NFTL 19% 22% 10% 14%

BL 37% 49% 24% 13%

• The experiments on EXT2 are on a DaVinci Evaluation Board with realistic transmission patterns and benchmark.

• Bonnie++: Sequential/Random files creation and deletion

• NTFS: Simulation over a 7-day disk trace