Hello @vishal6196    It's been a while on the Post yet as far as I recall, the App was writing to 1 CF only. In short, WAL is used for each RegionServer & subsequently, the Writes arrives at MemStore based on CF demarcation at Region Level. From WALReader, We confirmed the WAL have entries for 1 CF only, naturally indicating the MemStore of the concerned CF would be populated only. Additionally, I don't recall Crash being observed.   Are you facing similar concerns in your Environment. If Yes, Kindly share the following details in a New Post: What's the MemStore Flush failure trace from Logs, If the Problem is Persistent, Whether WALReader (Link [1]) shows Writes happening on all CF of the Regions & Count of CF of the Region. - Smarak   [1] https://hbase.apache.org/book.html#hlog_tool.prettyprint ... View more