[
https://issues.apache.org/jira/browse/CASSANDRA-14670?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Chris Lohfink updated CASSANDRA-14670:
--------------------------------------
Status: Review In Progress (was: Patch Available)
> 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}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
---------------------------------------------------------------------
To unsubscribe, e-mail: commits-unsubscr...@cassandra.apache.org
For additional commands, e-mail: commits-h...@cassandra.apache.org
