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https://issues.apache.org/jira/browse/CASSANDRA-8938?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14386793#comment-14386793
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Anuj commented on CASSANDRA-8938:
---------------------------------

Even though single partition read and range scan are technically different, 
from Application point of view they are just reads. I feel that scans should 
also make sstables "HOT" and make them eligible for STCS. 
Regarding nodetool cfstats, if Read count and Read Latency are not including 
scans , Don't you think we should have stats for scan count and latency ?

> Full Row Scan does not count towards Reads
> ------------------------------------------
>
>                 Key: CASSANDRA-8938
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-8938
>             Project: Cassandra
>          Issue Type: Bug
>          Components: API, Core, Tools
>         Environment: Unix, Cassandra 2.0.3
>            Reporter: Amit Singh Chowdhery
>            Assignee: Marcus Eriksson
>            Priority: Minor
>              Labels: none
>
> When a CQL SELECT statement is executed with WHERE clause, Read Count is 
> incremented in cfstats of the column family. But, when a full row scan is 
> done using SELECT statement without WHERE clause, Read Count is not 
> incremented. 
> Similarly, when using Size Tiered Compaction, if we do a full row scan using 
> Hector RangeslicesQuery, Read Count is not incremented in cfstats, Cassandra 
> still considers all sstables as cold and does not trigger compaction for 
> them. If we fire MultigetSliceQuery, Read Count is incremented and sstables 
> becomes hot, triggering compaction of these sstables. 
> Expected Behavior:
> 1. Read Count must be incremented by number of rows read during a full row 
> scan done using CQL SELECT statement or Hector RangeslicesQuery.
> 2. Size Tiered compaction must consider all sstables as Hot after a full row 
> scan.



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