Which file system does Android use? I have read both ext4 and YAFFS2.
Asked
Active
Viewed 2.7k times
20
-
@doug65536 ext4 as it is the Latest edition of the Extended File System by Linux. – amanuel2 Dec 08 '16 at 12:59
-
1[Android Kernel File System Support](https://source.android.com/docs/core/architecture/android-kernel-file-system-support) – Cristian Ciupitu Feb 22 '23 at 18:17
1 Answers
34
Android originally used YAFFS2 as the file system. After Android 2.3, the file system became ext4.
YAFFS2 is usually used for NAND flash in embedded systems such as mobile phones. It includes wear-leveling and a GC mechanism specifically for NAND flash, but it is only single-threaded.
According to an ARS Technica article, the reason that Android switched to ext4 from YAFFS2 for its file system is because YAFFS2 is single-threaded, and "would likely have been a bottleneck on dual-core systems." Android, even back in 2010 was looking forward when many cores could be used in Smartphones. Looking back, it was obvious that this was the right decision. Smartphones went to Dual Core around the time of Galaxy S2. More recently most Smart Phones are released in Quad-Core configuration, with 6 and 8 core configurations on the horizon.
Donald Duck
- 8,409
- 22
- 75
- 99
Greg Sherman
- 1,084
- 1
- 11
- 22