Issue 8704 - LMDB add option to use prev meta page
Summary: LMDB add option to use prev meta page
Status: RESOLVED TEST
Alias: None
Product: LMDB
Classification: Unclassified
Component: liblmdb (show other issues)
Version: unspecified
Hardware: All All
: --- enhancement
Target Milestone: 1.0.0
Assignee: OpenLDAP project
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2017-07-31 13:35 UTC by Howard Chu
Modified: 2020-03-16 22:51 UTC (History)
0 users

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Description Howard Chu 2017-07-31 13:35:09 UTC
Full_Name: Howard Chu
Version: LMDB 0.9
OS: 
URL: ftp://ftp.openldap.org/incoming/
Submission from: (NULL) (83.136.45.220)
Submitted by: hyc


Generally, running LMDB in NOSYNC mode means all integrity guarantees are gone,
in even of a system crash. However, if some other thread runs mdb_env_sync
periodically it's possible that the older DB state is still consistent, even if
slightly out of date. I have always intended to add an env flag for using the
older meta page, to potentially access a DB even after the latest txn snapshot
was corrupted.

A patch for this has been contributed, although support in the command-line
tools still needs to be added.
Comment 1 OpenLDAP project 2017-10-30 15:13:01 UTC
in mdb.master
Comment 2 Howard Chu 2017-10-30 15:13:01 UTC
changed notes
changed state Open to Test
moved from Incoming to Software Enhancements