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https://issues.apache.org/jira/browse/CASSANDRA-17062?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Sam Tunnicliffe updated CASSANDRA-17062:
----------------------------------------
    Status: Changes Suggested  (was: Review In Progress)

[~azotcsit] thanks for the PR, the new VT and tool output look good but I've 
got a couple of comments regarding the implementation:

I'm all for the distinction between weighted/unweighted caches at the 
presentation layer, but is there really a need to enforce this in the model 
code? The only real difference between the types at this level is the units of 
size/capacity, which are not explicit and only referenced in comments. I don't 
see any harm in the all cache metrics including a {{{}weightedSize{}}}, for 
unweighted caches this is just equal to {{size}} and simply isn't included in 
the VT/nodetool output.

As implemented, the mechanism of tracking hits/misses isn't correct. Because 
the auth caches use {{LoadingCache}} which transparently fetches missing 
entries, the hit rate is inflated and the miss rate undercounted. As it is, a 
miss would only be recorded if key is not cached *and* isn't found in the 
underlying storage. Likewise, a cache miss followed by a load from storage is 
counted as a hit.

I've pushed a couple of commits that address these points to 
[https://github.com/beobal/cassandra/tree/samt/17062-trunk]. When you get 
chance, take a look and see what you think.

> Expose Auth Caches metrics
> --------------------------
>
>                 Key: CASSANDRA-17062
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-17062
>             Project: Cassandra
>          Issue Type: Improvement
>          Components: Feature/Virtual Tables, Observability/Metrics, 
> Tool/nodetool
>            Reporter: Aleksei Zotov
>            Assignee: Aleksei Zotov
>            Priority: Normal
>             Fix For: 4.x
>
>
> Unlike to other caches (row, key, counter), Auth Caches lack some monitoring 
> capabilities. Here are a few particular changes to get this inequity fixed:
>  # Add auth caches to _system_views.caches_ VT
>  # Expose auth caches metrics via JMX
>  # Add auth caches details to _nodetool info_
>  



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