libdb/dist/ChangeLog

= Berkeley DB 5.3 Changelog =

== Changes between 11.2.5.3.15 and 11.2.5.3.21 ==

Fixed incompatibility problems of Java DPL with JDK7, so DPL will now
work with JDK7. [#20586]

Added a flag to allow database locking to be disabled from the SQL 
API. [#20928] 

Fixed a bug that could allocate a heap data page in a region after the 
region creation has been undone.  [#20939]

Redundant whitespaces are now ignored in DB_CONFIG lines pertaining to
directories, e.g. set_data_dir. [#20158]

Fixed a bug that caused DB_ENV->backup to stop early if DB_BACKUP_FILES was 
not set and a non-DB file was in the data directory. [#21076]

Fixed a rare race condition that could cause a crash if two processes opened 
the same database at the same time. [#21041]

Fixed missing cross compiling capability for the JDBC driver. [#21101] 

Allow the same system/machine to host both a master and a replica 
database through the use of relative pathnames. [#21105]

Fixed a bug in the Java API where EnvironmentConfig.setCreateDir would fail 
to configure the environment. [#21127]

Fixed an assert failure in btreeCompare when allocating memory
in the wrong thread was causing a memory leak. [#21232]

Fixed a bug in the Java API where concurrent operations that change the 
database schema could lead to a hang. [#21265]

Added JDBC code to the code base and updated the windows build files
to include the JDBC solution. [#21294]

Fixed a bug where the heap's region size was not getting swapped correctly
in mixed-endian environments. [#21295]

Fixed a bug in the db_sql_jdbc project file for vs2010 that was preventing
it from building correctly. [#21332]

== Database or Log File On-Disk Format Changes ==

Existing database file formats were unchanged in library version 11.2.5.3.

The log file format changed in library version 11.2.5.3. 

== New Features ==

Added support for verifying named in-memory dbs. [#16941]

Added an integer key comparison function to improve performance through
the SQL API. [#19609]

Support build on the platforms where pthread_t is a struct. [#19876]

Added an API call so the user can specify the size of the region in a 
heap db. [#19914]

Improved Replication Manager's ability to recover from the (perhaps
rare) phenomenon of two sites trying to connect to each other
simultaneously, which used to result in loss of both connections,
requiring a retry after the CONNECTION_RETRY timeout period.  [#19980]

Enhanced the interface for copying databases for a hot backup.  Added configure 
support for --enable-atomicfileread. [#20129]

Enhaced the log reading routine to detect that a log file is missing rather 
than returning that a zero length record was found. [#20130]

Added pragma bdbsql_shared_resources to set or report the maximum amount of 
memory to be used by shared structures in the main environment region and 
bdbsql_lock_tablesize to set or report the number of buckets in
the lock object hash table.  These are advanced tuning features for 
applications with large number of tables or needs to reduce locking on
concurrent long running transactions. [#20156]

Added set_metadata_dir() and get_metadata_dir() to enable storage of
persistent metadata files in a location other than the environment
home directory.  [#20174]

Improved the error handling through the SQL API.  Errors can be sent to a 
file with the use of the BDBSQL_ERROR_FILE pragma. [#20213]

Database handles can now be configured to give exclusive access to 
the database.  [#20331]

XA transactions will now use transaction snapshots if the XA databases 
they operate on were configured with DB_MULTIVERSION. [#20332]

Added additional stats fields into the C# API [#20693]

Added pragma bdbsql_single_process to keep the Berkeley DB environment 
information on the heap instead of in shared memory.  This option cannot
be used if the database is accessed from multiple processes.  [#20789]

Improved the ability of DB->compact to move DB_HASH database pages to the 
begining of the file. [#20815]

== Database Environment Changes ==

Fixed a bug that could cause a segmentation violation when closing 
an environment handle which has open database handles on partition 
databases. [#20281]

Fixed a bug that could cause a segmentation violation if a region was 
extended leaving a very small fragment at the end. [#20414]

Changed the behavior of the DB_REGISTER | DB_RECOVER flag combination, so 
that recovery is always run if the environment panic bit is set. [#20767]

== Access Method Changes ==

Fixed a bug were database configuration settings could be lost when the 
database was opened if the open operation was blocked for any amount 
of time. [#20860]

Fixed a bug that bulk update operations did not work correctly on 
compressed databases. [#19017]

Improved the log flushing performance when ftruncate() is not available 
on a system.  [#19725]

When performing partial puts in a heap database, empty pieces will no longer 
be left in a split record chain. [#20052]

Fixed a bug where, on systems without FTRUNCATE, db_verify will return an 
error for truncated heap databases. [#20195]

Fixed a bug where BDB could run out of mutexes when many databases are 
renamed.  [#20228] 

Fixed a bug where the metadata page in hash databases would not be flushed 
to disk.  [#20265]

Fixed a bug that could leave deleted pages from a HEAP database in the 
buffer cache. [#20309]

Fixed a bug where the library would fail to put records with overflow keys 
into hash duplicate database. [#20329]
	
Fixed a bug in DB->compact of btrees that could cause a bad pointer 
reference. [#20360]

Fixed a bug that could cause the last page number stored on the metadata 
page to be wrong after rolling forward a db->compact operation that freed 
more pages than will fit in a single log record. [#20646]

Fixed a bug that could cause DB->stat to block on a mutex while holding a 
lock on the metadata page.  [#20770]

Fixed a bug that could cause DB->compact of a DB_HASH database to fail to 
mark a page it updated as dirty. [#20778]

Fixed a bug where internal HEAP structures were not rebuilt during database 
handle refresh.  [#20821]

Fixed a bug with secondary indices, off-page duplicates and 
DB_READ_COMMITTED which could erroneously release the lock on the page 
holding a returned record. [#20853]

Fixed a bug that could cause a hang or improperly report an empty queue when
the queue record numbers wrapped around at 2^32. [#20956]

Fixed a bug on Linux or Windows that could generate a checksum error
if a database file was being opened while the meta data page happened
to be flushed from the cache. [#20996]

== SQL API Changes ==

Fixed several memory leaks in the Online Backup API. [#19850]

Fixed a bug in the SQL API when using large blob items and multiple concurrent 
connections. [#19945]

To avoid a race condition that could cause a snapshot reader to see a wrong 
version it is now not permitted to open a DB handle specifying DB_MULTIVERSION 
if that database is currently opened by a handle which did not specify 
DB_MULTIVERSION.  [#19940]

Pragma replication=on can now enable replication on an existing database.  
Turning replication off is now permanent. [#20180]

Fixed a bug in the SQL API where it was possible for a schema update to be 
ignored when accessing a database from multiple processes. [#20319]

Fixed a bug where aborting an exclusive transaction followed by an 
auto-commit read operation causes an assert failure. [#20567]

Fixed a bug in the SQL API where using the journal_mode pragma could cause a 
crash when used as the first operation in a connection on an existing 
database. [#20620]

Turn off the DBSQL encryption option on Windows/WinCE by default to match the 
behavior on the other platforms. [#20671]

Renamed the BDBSQL_OMIT_SHARING preprocessor flag to 
BDBSQL_SINGLE_PROCESS. [#20789]

Fixed a bug dealing with handle lock modes not reflecting the correct state
which was causing a deadlock in the SQL API. [#20862]

== Java-specific API changes ==

Added ReplicationManagerConnectionStatus class and 
ReplicationManagerSiteInfo.getConnectionStatus().  Deprecated 
ReplicationManagerSiteInfo.isConnected(). [#18068]

Updated EID_MASTER to be "public static final" so that it would be exposed
in Java docs. [#20184]

Fixed a bug where calls that return Stat objects could cause a 
segfault. [#20377]
	
== Replication Changes ==

Fixed quorum computation when most sites are unelectable. [#15251]

Made Replication more resilient to random input on its port. [#15712]

Fixed a bug where the datadir structure was not maintained during an 
internal init. [#19041]

Fixed a repmgr memory leak when using DB_PRIVATE. [#19363]

Fixed a minor bug to handle ENOMEM when using an in-memory
temp database. [#20197]

Fixed a bug where multiple long running transactions across
checkpoints could cause Log Sequence errors on client systems. [#20421]

Fixed a bug where multiple Replication Manager processes would sometimes 
not all conform to replication-group-aware log archiving. [#20342]

== Locking Subsystem Changes ==

Fixed a bug that could cause an early lock timeout if a previous error 
left a lock timeout value set. [#19973]

== Logging Subsystem Changes ==

Fixed a bug which could cause an incompletely written log record to be
recognized as valid, resulting in recovery failing with the message "Illegal
record type <integer, usually 0> in log". [#17851]

Fixed a bug where printlog would fail on in-memory heap databases.  [#20269]

== Memory Pool Subsystem Changes ==

Fixed a bug which overstated the number of clean and dirty pages evicted from
the cache. [#20410]

Fixed a bug that left a small fragment at the end of a region when 
extending. [#20414]

Fixed a bug where the file bucket was always zero when creating a mpoolfile 
using the mpool API. [#20468]

Fixed a bug with multiversion concurrency control which could cause 
versions of pages to remain in the cache even though they are no longer 
needed. [#20570]

The memory pool allocator will now start freezing MVCC versions of buffers 
if it sees more than 1/4 of the available buffers are taken up by 
versions. [#20836]

== Mutex Subsystem Changes ==

Fixed a bug in which DB_ENV->mutex_set_align() could cause
DB_ENV->mutex_stat_print(dbenv, DB_STAT_ALL) to display only the 
first mutex. [#20522]

Fixed a bug with DB_ENV->mutex_stat_print() in which the information on 
some mutexes would not be displayed, if any mutex had been freed and not 
yet reallocated. [#20533]

== Transaction Subsystem Changes ==

Fixed a bug where a malloc failure could result in a segfault
when doing a put on a database with secondaries.  [#20641]

== Utility Changes ==

Fixed a bug that would cause verify to call the wrong compare function if
there are user defined compare functions used and the database has multilevel
off page sorted duplicate trees. [#20284]

Fixed a bug that could cause recovery to fail if DB->compact moved the meta 
data page of a HASH subdatabase.  [#20708] 

Fixed two problems with db_hotbackup's handling of transaction logs. A hotbackup
would always try to open the logs in the environment home, even if a log
directory had been specified. The second fix corrected an error path, in which
the memory was freed by the wrong function, possibly causing a guard byte error.
[#21313]

== Configuration, Documentation, Sample Apps, Portability and Build Changes ==

The DB_CONFIG configuration commands which specify directory pathnames
("set_data_dir", "set_lg_dir", and "set_tmp_dir") now accept names containing
whitespace characters. [#20158]

== Known Bugs ==

If two SQL processes are concurrently altering the schema of the same tables 
in a database, there is a race condition that can cause the application 
to hang. [#20513]

Replication groups including machines of different endianness do 
not support the heap access method. [#21016]

If a txn that is attempting to remove a region page from a heap database is
aborted and another txn is trying to update that same page then it can 
cause the original txn to abort.   This is timing dependant. [#20939]