This is the list of Items that can be added to Hive LLAP caching layer that can help with usability and performance stability

1. LLAP Cache Roadmap

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LLAP Cache Roadmap
Allocates Free buffer
on background to
avoid synchronization
using allocation
statistics
Lock free
bookkeeping for
LRFU
Simpler Replacement
strategy like LRU
Emergency Out-of-
Buffers Emergency
pool.

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LLAP Cache Roadmap
Data access frequency
collected at query level for
each column (scan count
etc.) to indicate data
hotness
Rule based heuristics to
identify cold objects
(column, partition, table)
with large memory
footprint as page loadable
candidates
User adjustable threshold
for cold and hot objects
Flexible interface for user
to act on individual
recommended object to
convert from column
loadable to page loadable
or vice versa.

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LLAP Cache Roadmap
Cache Usability
• List cache usage by table
Table A -> bytes
Column C1
Column Cn
Table B -> bytes
Metadata File 1 -> bytes
• Drop table from cache.
• Evict temp tables on sessions closing
• Cache preload commands in case we can predict the workload
• Show/run fragmentation/defragmentation.