Hi All, The compaction would organize the sstables, e.g. with LCS, the sstables would be categorized into levels, and the read path should read sstables level by level until the read is fulfilled, correct?
For STCS, it would search sstables in buckets from smallest to largest? What about other compaction cases? They would iterate all sstables? But in the codes, I'm confused a lot: In org.apache.cassandra.db.SinglePartitionReadCommand#queryMemtableAndDiskInternal, it seems that no matter whether the selected columns (except the collection/cdt and counter cases, let's assume here the selected columns are simple cell) are collected and satisfied, it would search both memtable and all sstables, regardless of the compaction strategy. Why? Moreover, for collection/cdt (non-frozen) and counter types, it would need to iterate all sstable to ensure the whole set of the fields are collected, correct? If so, such multi-cell or counter types are heavyweight in performance, correct? --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@cassandra.apache.org For additional commands, e-mail: user-h...@cassandra.apache.org
