* Check that 00/00 and ff/ff exist at startup, otherwise exit with error.
* 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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