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https://issues.apache.org/jira/browse/CASSANDRA-14670?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16876784#comment-16876784
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Aleksey Yeschenko commented on CASSANDRA-14670:
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Are you guys sure that putting `count` in the partition key is a good idea? The 
partition key isn't really the right sort of place for mutable components like 
this, and putting it there makes it impossible to look up by partition key. I 
see the intention, but this might not be the right solution to the sorting 
issue - relaxing `ORDER BY` is.

> Table Metrics Virtual Table
> ---------------------------
>
>                 Key: CASSANDRA-14670
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-14670
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Legacy/CQL, Legacy/Observability
>            Reporter: Chris Lohfink
>            Assignee: Chris Lohfink
>            Priority: Low
>              Labels: pull-request-available, virtual-tables
>             Fix For: 4.0.x
>
>          Time Spent: 10m
>  Remaining Estimate: 0h
>
> Different than CASSANDRA-14572 whose goal is to expose all metrics. This is 
> to expose a few hand tailored tables that are particularly useful in 
> debugging slow Cassandra instances (in my experience). These are useful in 
> finding out which table it is that is having issues if you see a node 
> performing poorly in general. This can kinda be figured out with cfstats 
> sorting and some clever bash-foo but its been a bit of a operational UX pain 
> for me personally for awhile.
> examples:
> {code}
> cqlsh> select * from system_views.max_partition_size limit 5;
>  max_partition_size | keyspace_name | table_name
> --------------------+---------------+----------------
>              126934 |        system | size_estimates
>                9887 | system_schema |        columns
>                9887 | system_schema |         tables
>                6866 |        system |          local
>                 258 |     keyspace1 |      standard1
> (5 rows)
> cqlsh> select * from system_views.local_reads limit 5 ;
>  count | keyspace_name | table_name      | 99th      | max       | median  | 
> per_second
> -------+---------------+-----------------+-----------+-----------+---------+------------
>     23 |        system |           local | 186563160 | 186563160 | 1629722 |  
>   3.56101
>     22 | system_schema |          tables |   4055269 |   4055269 |  454826 |  
>   3.72452
>     14 | system_schema |         columns |   1131752 |   1131752 |  545791 |  
>   2.37015
>     14 | system_schema | dropped_columns |    126934 |    126934 |   88148 |  
>   2.37015
>     14 | system_schema |         indexes |    219342 |    219342 |  152321 |  
>   2.37015
> (5 rows)
> cqlsh> select * from system_views.coordinator_reads limit 5;
>  count | keyspace_name | table_name | 99th | max | median | per_second
> -------+---------------+------------+------+-----+--------+------------
>      2 |        system |      local |    0 |   0 |      0 |   0.005324
>      1 |   system_auth |      roles |    0 |   0 |      0 |   0.002662
>      0 |         basic |       wide |    0 |   0 |      0 |          0
>      0 |         basic |      wide3 |    0 |   0 |      0 |          0
>      0 |     keyspace1 |   counter1 |    0 |   0 |      0 |          0
> (5 rows)
> {code}



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