Storage EXT4 journal in enhanced area of eMMC
Storage EXT4 journal in the enhanced area of eMMC
Blueprint information
- Status:
- Started
- Approver:
- Arnd Bergmann
- Priority:
- High
- Drafter:
- Saugata Das
- Direction:
- Needs approval
- Assignee:
- Balaji T K
- Definition:
- Approved
- Series goal:
- Accepted for kernel-merge-window
- Implementation:
-
Started
- Milestone target:
-
backlog
- Started by
- Saugata Das
- Completed by
Related branches
Related bugs
Sprints
Whiteboard
Meta:
Headline: Storage EXT4 journal in the enhanced area
Roadmap id: KWG2011-
Acceptance:
Refer storage mini-summit conclusions, http://
[jakub-pavelek 2013-01-02] Blocked, no developer. Can go deferred if not resolved
[jakub-pavelek 2013-02-06] Un-blocking, Balaji is back
[jakub-pavelek 2013-04-10] Blocked, no development in two months. Removing target kernel release - we do not have one.
[jakub-pavelek 2013-06-10] Un-blocking, Balaji is back.
First tests with a small fs entirely on enhanced area showed worse performance for Micron and better performance with Sandisk hardware compared to non-enhanced area. We assume this is only true for non-aged file systems and that for any hardware, the long-term effect of enhanced area should be positive.
[Balaji]
Write on enhanced area stills show no improvement over user area with Micron eMMC
To retry with another Micron eMMC device and confirm.
balajitk: mkfs command to keep inode and bitmaps metadata in one super block
mke4fs -G 64 flex_bg
balajitk
mkfs.ext4 -O flex_bg -G 64
to move block bitmap, inode bitmap and inode table on subsequent blocks
Work Items
Work items for 12.11:
[saugata.das] Enable enhanced area on eMMC : DONE
Work items for 13.06:
[balajik] Experiment with mkfs using journal on enhanced area : INPROGRESS
[balajitk] Experiment with mkfs to put inode metadata in single block group: DONE
[balajik] Experiment with mkfs to put all metadata in front (single block group) : DONE
[balajitk] Patch mkfs to move journal data from middle to start of the partition (Jun 28): DONE
Work items for 13.07:
[balajitk] Club journal and metadata together in enhanced area : DONE
[balajitk] Performance benchmark with journal and metadata on enhanced area : INPROGRESS
[balajitk] Kernel build time as performance benchmark : INPROGRESS
Work items for backlog:
[balajik] Study mkfs tool : TODO
[balajik] Implement automatic marking of enhanced area in mkfs for the above : TODO
Dependency tree
* Blueprints in grey have been implemented.
