Write Ahead Physical Block Logging

__NOTOC__

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.{{r|w|b-n-w|wapbl.4|wapbl.9}} 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 shut down in an unclean fashion.{{r|wapbl.4}}

History

WAPBL was initially committed into NetBSD in 2008, and first appeared with NetBSD 5.0 (2009).{{r|wapbl.h|b-n-w|n50}}

With NetBSD 6.0 (2012), soft updates (known as soft dependencies in NetBSD) was removed in favour of WAPBL.{{r|n60|softdep_rm}}

See also

{{Portal

| Free and open-source software

}}

References

{{Reflist

|refs=

{{cite web

|author= Wasabi Systems Inc.

|date= 2008

|url= http://www.wasabisystems.com/technology/wjfs

|title= Wasabi JFS

|archive-url= https://web.archive.org/web/20080306194749/http://www.wasabisystems.com/technology/wjfs

|archive-date= 2008-03-06

}}

{{cite web

|url= http://broadcast.oreilly.com/2009/05/netbsd-wapbl.html

|title= NetBSD WAPBL

|author= Federico Biancuzzi

|publisher= O'Reilly Media

|date= 2008-05-18 |archive-url= https://web.archive.org/web/20100107141731/http://broadcast.oreilly.com/2009/05/netbsd-wapbl.html

|access-date=2019-03-24

|archive-date= 2010-01-07

}}

{{cite web

|author= The NetBSD Foundation, Inc. |date= 2008

|url= http://bxr.su/n/sys/sys/wapbl.h

|title= sys/wapbl.h

|website= BSD Cross Reference

|publisher= NetBSD

}}

{{cite web

|author= The NetBSD Foundation, Inc.

|date= 2008–2012

|url= http://bxr.su/n/share/man/man4/wapbl.4

|title= WAPBL(4) — Write Ahead Physical Block Logging file system journaling

|website= BSD Cross Reference

|publisher= NetBSD

}}

{{cite web

|author= The NetBSD Foundation, Inc.

|date= 2015

|url= http://bxr.su/n/share/man/man9/wapbl.9

|title= WAPBL(9) — write-ahead physical block logging for file systems

|website= BSD Cross Reference

|publisher= NetBSD

}}

{{cite web

|author= The NetBSD Project |date=2009-04-29

|url= //www.netbsd.org/releases/formal-5/NetBSD-5.0.html

|title= Announcing NetBSD 5.0

|publisher= NetBSD

|quote= Some highlights are: a preview of metadata journaling for FFS file systems (known as WAPBL, Write Ahead Physical Block Logging)

}}

{{cite web

|author= The NetBSD Project |date=2012-10-17

|url= //www.netbsd.org/releases/formal-6/NetBSD-6.0.html#removals

|title= Components removed from NetBSD

|work= Announcing NetBSD 6.0

|publisher= NetBSD

|quote= "softdep" support is no longer available in FFS; use wapbl(4) logging instead.

}}

{{cite web

|author= Adam Hamsik |date=2009-02-23

|url= //blog.netbsd.org/tnf/entry/soft_dependencies_removed

|title= Soft dependencies removed

|publisher= NetBSD

}}

}}