Write Ahead Physical Block Logging

Write Ahead Physical Block Logging (WAPBL) provides meta data journaling for file systems in conjunction with Fast File System (FFS) to accomplish rapid filesystem consistency after an unclean shutdown of the filesystem and better general use performance over regular FFS.[1][2][3][4] With the journal, fsck is no longer required at system boot; instead, the system can replay the journal in order to correct any inconsistencies in the filesystem if the system has been shutdown in an unclean fashion.[3]

History

WAPBL was initially committed into NetBSD in 2008, and first appeared with NetBSD 5.0 (2009).[5][2][6]

With NetBSD 6.0 (2012), soft updates (known as soft dependencies in NetBSD) was removed in favour of WAPBL.[7][8]

gollark: Idea: not using ***C***.
gollark: People use **Windows**.
gollark: It would just need a bootloader and stuff and probably involve horrible madness like directly rewriting the BF code.
gollark: I'm sure you can do it by executing programs within BF.
gollark: Even on bare-metal I think poking some memory areas can directly display text.

See also

References
  1. Wasabi Systems Inc. (2008). "Wasabi JFS". Archived from the original on 2008-03-06.
  2. Federico Biancuzzi (2008-05-18). "NetBSD WAPBL". O'Reilly Media. Archived from the original on 2010-01-07. Retrieved 2019-03-24.
  3. The NetBSD Foundation, Inc. (2008–2012). "WAPBL(4) — Write Ahead Physical Block Logging file system journaling". BSD Cross Reference. NetBSD. Lay summary.
  4. The NetBSD Foundation, Inc. (2015). "WAPBL(9) — write-ahead physical block logging for file systems". BSD Cross Reference. NetBSD. Lay summary.
  5. The NetBSD Foundation, Inc. (2008). "sys/wapbl.h". BSD Cross Reference. NetBSD.
  6. The NetBSD Project (2009-04-29). "Announcing NetBSD 5.0". NetBSD. Some highlights are: a preview of metadata journaling for FFS file systems (known as WAPBL, Write Ahead Physical Block Logging)
  7. The NetBSD Project (2012-10-17). "Components removed from NetBSD". Announcing NetBSD 6.0. NetBSD. “softdep” support is no longer available in FFS; use wapbl(4) logging instead.
  8. Adam Hamsik (2009-02-23). "Soft dependencies removed". NetBSD.


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