HBASE-25642 Fix or stop warning about already cached block (#3638)
Our logs have as a fairly common occurrence: 2021-03-05 22:24:31,034 WARN
[StoreFileOpener-foo-1] hfile.BlockCacheUtil: Caching an already cached
block: blah.bub. This is harmless and can happen in rare cases (see HBASE-8547)
Because it is harmless, log at DEBUG level, not WARN.
Signed-off-by: Baiqiang Zhao <zhaobaiqiang@apache.org>
Signed-off-by: Duo Zhang <zhangduo@apache.org>
Signed-off-by: Viraj Jasani <vjasani@apache.org>
Reviewed-by: Rushabh Shah <rushabh.shah@salesforce.com>