What about write-back cache for remoteFS

Hello @kssenii, we have a write-through cache for remoteFS in ClickHouse. What about a write-back cache?

We can track dirty file segments for a moment(eg. 5 seconds), and keeping flush to remote storage in the background. Just like pd-flush thread in kernel filesystem flush dirty page-cache.

We can get benefit from keeping file segments in cache for a moment when user insert small batch frequently, then the small batch data will be merged and delete in cache, not upload to remoteFS.