github.com/dgraph-io/badger

Bug Fixes:

• Fix a panic caused due to item.vptr not copying over vs.Value, when looking for a move key.

Bug Fixes:

• Fix the way move key gets generated.

• If a transaction has unclosed, or multiple iterators running simultaneously, throw a panic. Every iterator must be properly closed. At any point in time, only one iterator per transaction can be running. This is to avoid bugs in a transaction data structure which is thread unsafe.

• Warning: This change might cause panics in user code. Fix is to properly close your iterators, and only have one running at a time per transaction.

Bug Fixes:

• Fix for infinite yieldItemValue recursion. #503
• Fix recursive addition of badgerMove prefix. https://github.com/dgraph-io/badger/commit/2e3a32f0ccac3066fb4206b28deb39c210c5266f
• Use file size based window size for sampling, instead of fixing it to 10MB. #501

Cleanup:

• Clarify comments and documentation.
• Move badger tool one directory level up.

• Introduce NumVersionsToKeep option. This option is used to discard many versions of the same key, which saves space.
• Add a new SetWithDiscard method, which would indicate that all the older versions of the key are now invalid. Those versions would be discarded during compactions.
• Value log GC moves are now bound to another keyspace to ensure latest versions of data are always at the top in LSM tree.
• Introduce ValueLogMaxEntries to restrict the number of key-value pairs per value log file. This helps bound the time it takes to garbage collect one file.

• Make mmap-ing of value log optional.
• Run GC multiple times, based on recorded discard statistics.
• Add MergeOperator.
• Force compact L0 on clsoe (#439).
• Add truncate option to warn about data loss (#452).
• Discard key versions during compaction (#464).
• Introduce new LSMOnlyOptions, to make Badger act like a typical LSM based DB.

Bug fix:

• (Temporary) Check max version across all tables in Get (removed in next release).
• Update commit and read ts while loading from backup.
• Ensure all transaction entries are part of the same value log file.
• On commit, run unlock callbacks before doing writes (#413).
• Wait for goroutines to finish before closing iterators (#421).