published in https://reviews.facebook.net/D5997.
Summary:
This patch allows compaction to occur in multiple background threads
concurrently.
If a manual compaction is issued, the system falls back to a
single-compaction-thread model. This is done to ensure correctess
and simplicity of code. When the manual compaction is finished,
the system resumes its concurrent-compaction mode automatically.
The updates to the manifest are done via group-commit approach.
Test Plan: run db_bench
Summary:
Created a tool that runs multiple threads that concurrently read and write to levelDB.
All writes to the DB are stored in an in-memory hashtable and verified at the end of the
test. All writes for a given key are serialzied.
Test Plan:
- Verified by writing only a few keys and logging all writes and verifying that values read and written are correct.
- Verified correctness of value generator.
- Ran with various parameters of number of keys, locks, and threads.
Reviewers: dhruba, MarkCallaghan, heyongqiang
Reviewed By: dhruba
Differential Revision: https://reviews.facebook.net/D5829
