* Implement sync flush option, where data is written synchronously on disk when a command is executed.
* Implement MULTI/EXEC as transaction abstract API to diskstore.c, with transaction_start, transaction_end, and a journal to recover.
* Stop BGSAVE thread on shutdown and any other condition where the child is killed during normal bgsave.
-* Use a mutex to log on the file, so that we don't get overlapping messages, or even better make sure to use a single write against it.
* Fix RANDOMKEY to really do something interesting
* Fix DBSIZE to really do something interesting
* Add a DEBUG command to check if an entry is or not in memory currently
-* Prevent io jobs from running while there is a BGSAVE thread.
REPLICATION
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