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Diffstat (limited to 'NEWS')
| -rw-r--r-- | NEWS | 99 |
1 files changed, 99 insertions, 0 deletions
@@ -1,3 +1,102 @@ +WiredTiger release 1.3.4, 2012-10-19 +------------------------------------ + +This release includes several important new features, including: + +* support for online compaction of files; +* support for tables, column groups and indices that use LSM trees for + storage; and +* improved statistics and configuration for LSM trees and Bloom filters. + +In addition, there are some significant performance improvements and bug +fixes. The full list of changes is: + +[#248] Add support for online compaction. + +[#310] Fixed a bug where overflow blocks could be accessed by a + long-running reader after they had been freed in a checkpoint. + +[#358] Allocate checkpoint blocks from the live system's list of available + blocks rather than always extending the file. + +[#361] Sync the directory after creating a file: this is apparently + required for durability on Linux, according to the Linux fsync man + page. + +[#362] Don't check if a page is on the avail or discard lists if we're + salvaging the file, that is okay. + +[#363] Remove obsolete code dealing with forced eviction. + +[#366] Fake checkpoints may have the delete flag set, ignore them when + rolling checkpoints forward. + +[#367] All metadata reads should ignore the application's transactional + context. + +[#369] Support LSM as a data source for tables, column groups and indices. + +* Add tuning options for LSM bloom filters, including controlling whether + the oldest level in the tree has a Bloom filter, whether newly-created + (level 0) files have Bloom filters, and passing arbitrary file + configuration for Bloom filters. + +* Add a merge generation to LSM chunks. Add a statistic that reports the + highest merge generation in a tree. + +* Add a new LSM statistic tracking searches that could benefit from bloom + filters. + +* Enable LSM statistics in the "wt stat" utility. + +* Interrupt LSM merge operations, rather than waiting on close. + +* Wait for a while before looking for LSM major merges, in case merges + catch up with inserts. + +* Fix LSM index searches. The main issue was LSM search_near was not + always returning the closest key to the search key, which calling code + expects. It now tries hard to find the smallest cursor larger than the + search key, and only if no larger record exists does it return the + largest record smaller than the search key. + +* Reset any old cursor position before an LSM search. This limits hazard + references in an LSM search to a single chunk. + +* Fix a memory leak in an error path in Bloom filters. + +* Tweak the search loops in hazard_{set,clear} in favor of + last-in-first-out ordering. + +* If there are many files open, some hotter than others, walk more files + looking for pages to evict. + +* Don't stop evicting until we reach the target, have eviction wake up + periodically regardless of whether the application signals it. This + latter requires a "timed condition wait" operation. + +* Tweaks to file handle flags for out-of-cache read performance on Linux + (disable readahead and access time updates). + +* Replace the WT_SESSION::dumpfile method with configuration strings to + WT_SESSION::verify. + +* Fix a bug where we weren't skipping unnecessary default checkpoints + because we weren't handling the generational number included in the + internal checkpoint name. + +* Add a "force" configuration flag to WT_SESSION::checkpoint, object + compaction needs it because the work it wants done is done by the block + manager. + +* Make compact and checkpoint operate on a table's indices. + +* When doing a page truncate, lock down the page before we unpack the + on-page cell -- it's possible the page could be instantiated, modified + and reconciled while we're sleeping, in which case the WT_REF.addr field + would no longer point on-page. + + WiredTiger release 1.3.3, 2012-10-11 ------------------------------------ |