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Diffstat (limited to 'NEWS')
| -rw-r--r-- | NEWS | 61 |
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@@ -1,3 +1,64 @@ +WiredTiger release 1.6.6, 2013-11-19 +------------------------------------ + +The WiredTiger 1.6.6 release is a bugfix and performance tuning release. + +This release of WiredTiger contains a database format change. Database files +from previous releases will need to be upgraded. + +A special note: the WiredTiger code base is now being regularly reviewed +using the Coverity Static Analysis Verification Engine. We'd like to +thank Coverity for their on-going support of Open Source projects like +WiredTiger! + +Significant changes include: + +* Performance changes include: limiting operations done inside update + serialization primitives, removing unnecessary memory barriers, replacing + spinlocks with atomic instructions, padding structures to avoid false + cache sharing, switching from per-file mutexes to per-page mutexes, + pre-allocating structures to avoid memory allocation while holding + mutexes, and using adaptive mutexes where available. + [#707, #718, #719] + +* A number of LSM stability and performance improvements: changes include + better merge algorithms, reduced locking, and higher concurrency. + +* A number of table compaction performance improvements, including changes + allowing compaction to no longer read unnecessary file blocks into the + cache, requires fewer passes over the file and support concurrent + checkpoints and eviction. This change required an underlying file + format change, see the upgrading documentation for details. + [#756, #761] + +* WiredTiger statistics have been significantly improved: + + Statistics logging has been changed to aggregate information from all + open handles. [#709, #717] + + For performance reasons, statistics are now disabled by default, see + the upgrading documentation for details. [#715] + + Statistics configuration has been changed so the connection and cursor + configuration are consistent, with matching changes to the "wt stat" + command-line utility; see the upgrading documentation for details. + +* Update WT_EVENT_HANDLER interface to contain a new "handle close" + interface and to pass a WT_SESSION handle into all callbacks, see the + upgrading documentation for details. [#649] + + Add timestamp, process ID and thread ID to messages generated via + WT_EVENT_HANDLER interface. [#753] + +* WiredTiger eviction improvements, supporting larger data-to-cache size + ratios. [#754] + +* Various fixes for handling overflow records. [#726, #743] + +* Overflow records are no longer tracked during bulk-loads, significantly + increasing bulk-load performance for some data sets. + + WiredTiger release 1.6.5, 2013-10-09 ------------------------------------ |