How to invalidate all cache

Hi all,

I am trying to do some benchmarks against bcache, espeically in cache miss scenario, but I don't find a user interface to invalidate all cache. Anyone can tell me how to do that.

Thanks in advance,
- Zheng
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You can try to detach the backing device, which will cause all dirty data to be written back, and attach it again.

Quoted 12 lines

Hi all,

I am trying to do some benchmarks against bcache, espeically in cache miss scenario, but I don't find a user interface to invalidate all cache. Anyone can tell me how to do that.

Thanks in advance,
- Zheng
--
To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html

Yes, detaching a backing device will make all dirty data to be written back to the backing device. But if I understand correctly it couldn't invalidate all data in cache device. That means that after attaching backing device the data in cache device is still valid.

Hello Zheng,

Quoted 4 lines · you

Yes, detaching a backing device will make all dirty data to be written back to the backing device. But if I understand correctly it couldn't invalidate all data in cache device. That means that after attaching backing device the data in cache device is still valid.

It would be a bug if cached data were considered valid after detaching and re-attaching. Because while a cache device an a backing device were separated, data could be written to a backing device, this would possibly make data in a "disconnected" cache obsolete.