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Diffstat (limited to 'src/third_party/wiredtiger/src/docs/upgrading.dox')
| -rw-r--r-- | src/third_party/wiredtiger/src/docs/upgrading.dox | 82 |
1 files changed, 72 insertions, 10 deletions
diff --git a/src/third_party/wiredtiger/src/docs/upgrading.dox b/src/third_party/wiredtiger/src/docs/upgrading.dox index 2e4990e8a33..0d8e5e1b428 100644 --- a/src/third_party/wiredtiger/src/docs/upgrading.dox +++ b/src/third_party/wiredtiger/src/docs/upgrading.dox @@ -1,5 +1,77 @@ /*! @page upgrading Upgrading WiredTiger applications +</dl><hr> +@section version_311 Upgrading to Version 3.1.1 +<dl> + +<dt>WT_CURSOR::modify transaction requirements</dt> +<dd> +In previous releases of WiredTiger, it was possible to use implicit +transactions in combination with WT_CURSOR::modify operations. This +requires applications be extraordinarily careful to avoid multiple +threads which are changing the same values racing with each other. In +the 3.1.1 release, WT_CURSOR::modify operations must be performed in an +explicit transaction, and will fail if that's not the case. +</dd> + +</dl><hr> +@section version_310 Upgrading to Version 3.1.0 +<dl> + +<dt>WiredTiger on-disk log file format change</dt> +<dd> +The WiredTiger on-disk file format for write-ahead log files has changed +as the log file version number was incremented. See +<a href=https://jira.mongodb.org/browse/WT-4029>WT-4029</a> for details. +</dd> + +<dt>::wiredtiger_open compatibility configuration changes</dt> +<dd> +The compatibility setting now takes additional options that can define +the minimum or maximum required version of existing data files. See +<a href=https://jira.mongodb.org/browse/WT-4056>WT-4056</a> and +<a href=https://jira.mongodb.org/browse/WT-4098>WT-4098</a> for details. +</dd> + +<dt>::wiredtiger_open cache configuration changes</dt> +<dd> +The cache configuration options \c eviction_checkpoint_target, \c +eviction_dirty_target, \c eviction_dirty_trigger, \c eviction_target and \c +eviction_trigger have changed. The options can now take an absolute size. It would +be a percentage of the cache size if the value is within the range of 0 to 100 +or an absolute size when greater than 100. This API change is compatible with +existing usage. See <a href=https://jira.mongodb.org/browse/WT-3632>WT-3632</a> +for details. +</dd> + +<dt>Changed transaction semantics around schema operations</dt> +<dd> +WiredTiger does not offer fully transactional create and drop operations. +We have made some changes to how create and drop are implemented +if done within the scope of an explicit transaction. If an application +is relying on particular visibility/atomicity guarantees around table +create or drop, care should be taken when upgrading. See +<a href=https://jira.mongodb.org/browse/WT-3964>WT-3964</a> for details. +</dd> + +<dt>On-disk format change for metadata</dt> +<dd> +There was a change to the content stored in the WiredTiger owned metadata +files, which means metadata created or updated by this version of WiredTiger +is not compatible with earlier versions. See +<a href=https://jira.mongodb.org/browse/WT-3905>WT-3905</a> for details. +</dd> + +<dt>Implement a per-session cursor cache</dt> +<dd> +WiredTiger now holds a cache of recently closed cursors in each +session. This improves performance for applications that open and +close cursors frequently, but increases memory overhead. The cache +is enabled by default, but can be disabled. See +<a href=https://jira.mongodb.org/browse/WT-1228>WT-1228</a> for details. +</dd> + +</dl><hr> @section version_300 Upgrading to Version 3.0.0 <dl> @@ -28,16 +100,6 @@ The performance visualization tool \c wtstats has been removed and is no longer supported. </dd> -<dt>::wiredtiger_open cache configuration changes</dt> -<dd> -The cache configuration options \c eviction_checkpoint_target, \c -eviction_dirty_target, \c eviction_dirty_trigger, \c eviction_target and \c -eviction_trigger have changed. The options can now take absolute size. It would -be a percentage of the cache size if the value is within the range of 0 to 100 -or an absolute size when greater than 100. This API change is compatible with -existing usage. -</dd> - </dl><hr> @section version_292 Upgrading to Version 2.9.2 <dl> |