[HBASE-19959] How much RAM space is to be really consumed by the memstore?

• Type: Brainstorming
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: regionserver
• Assignee: Unassigned
• Reporter: Chance Li
• Created: 08/Feb/18 05:59
• Updated: 11/Feb/18 09:54

Description

Let's consider this scenario where memstoreLAB and ChunkPool is enable and max memstore size is 10G, and after some time all pooled chunk have been created, then flush all data, now memstore size is 0 but RAM actually have consumed 10G, then continue writing big cell which will not use the chunk pool but jvm heap, then memstore size will be increased to 10G(maybe more because overhead). now we can see RAM actually consumed 20G (10G of pooled chunk + 10G java objects), but the max memstore size is only 10G.

what I say is the max memstore size not only take care about the cell "size" but also RAM really used. This will be a strict memory management: the max memstore size limit the RAM space which the memstore or related module can be used.

This really rarely occured. It's just for a robust memory managemant semantically.
What do you think?