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https://issues.apache.org/jira/browse/CASSANDRA-15194?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16899416#comment-16899416
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Benedict commented on CASSANDRA-15194:
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I'll try to take a quick look at this early next week too. One little thing
jumps out at me, based on Jon's comment, and that's that we should avoiding
dividing by a constant for our floating point arithmetic if possible - it's
better to save the reciprocal as a constant, and to multiply by it. I'm unsure
if the compiler would be willing to apply this optimisation for us, since this
might lead to a slightly different answer.
It looks like we also do this for the conversion to MiB because we convert to a
double before dividing by the long constant, although this might be
compiler-optimisable given it's a power-of-2.
Neither of these things are super important, of course.
> Improve readability of Table metrics Virtual tables units
> ---------------------------------------------------------
>
> Key: CASSANDRA-15194
> URL: https://issues.apache.org/jira/browse/CASSANDRA-15194
> Project: Cassandra
> Issue Type: Bug
> Components: Feature/Virtual Tables
> Reporter: Jon Haddad
> Assignee: Chris Lohfink
> Priority: Normal
> Fix For: 4.0
>
>
> I just noticed this strange output in the coordinator_reads output::
> {code}
> cqlsh:system_views> select * from coordinator_reads ;
> count | keyspace_name | table_name | 99th | max |
> median | per_second
> -------+--------------------+--------------------------------+------+-----+--------+------------
> 7573 | tlp_stress | keyvalue | 0 | 0 |
> 0 | 2.2375e-16
> 6076 | tlp_stress | random_access | 0 | 0 |
> 0 | 7.4126e-12
> 390 | tlp_stress | sensor_data_udt | 0 | 0 |
> 0 | 1.7721e-64
> 30 | system | local | 0 | 0 |
> 0 | 0.006406
> 11 | system_schema | columns | 0 | 0 |
> 0 | 1.1192e-16
> 11 | system_schema | indexes | 0 | 0 |
> 0 | 1.1192e-16
> 11 | system_schema | tables | 0 | 0 |
> 0 | 1.1192e-16
> 11 | system_schema | views | 0 | 0 |
> 0 | 1.1192e-16
> {code}
> cc [~cnlwsu]
> btw I realize the output is technically correct, but it's not very readable.
> For practical purposes this should just say 0.
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