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https://issues.apache.org/jira/browse/HBASE-15376?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15177041#comment-15177041
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Heng Chen commented on HBASE-15376:
-----------------------------------

{code}
The https://hbase.apache.org/book.html#hbase.versioning page says that there is 
no operational compatibility between minor versions, so according to the 
previously agreed on guidelines, we can (but do not need to) in fact change the 
name of the metrics in 1.3+.
{code}

You are right.  So we have no plan to backport it to branch-1.0+ (just add 
metrics for scan time) ?

> ScanNext metric is size-based while every other per-operation metric is time 
> based
> ----------------------------------------------------------------------------------
>
>                 Key: HBASE-15376
>                 URL: https://issues.apache.org/jira/browse/HBASE-15376
>             Project: HBase
>          Issue Type: Sub-task
>            Reporter: Enis Soztutar
>         Attachments: HBASE-15376.patch
>
>
> We have per-operation metrics for {{Get}}, {{Mutate}}, {{Delete}}, 
> {{Increment}}, and {{ScanNext}}. 
> The metrics are emitted like: 
> {code}
>    "Get_num_ops" : 4837505,
>     "Get_min" : 0,
>     "Get_max" : 296,
>     "Get_mean" : 0.2934618155433431,
>     "Get_median" : 0.0,
>     "Get_75th_percentile" : 0.0,
>     "Get_95th_percentile" : 1.0,
>     "Get_99th_percentile" : 1.0,
> ...
>     "ScanNext_num_ops" : 194705,
>     "ScanNext_min" : 0,
>     "ScanNext_max" : 18441,
>     "ScanNext_mean" : 7468.274651395701,
>     "ScanNext_median" : 583.0,
>     "ScanNext_75th_percentile" : 583.0,
>     "ScanNext_95th_percentile" : 13481.0,
>     "ScanNext_99th_percentile" : 13481.0,
> {code}
> The problem is that all of Get,Mutate,Delete,Increment,Append,Replay are time 
> based tracking how long the operation ran, while ScanNext is tracking 
> returned response sizes (returned cell-sizes to be exact). Obviously, this is 
> very confusing and you would only know this subtlety if you read the metrics 
> collection code. 
> Not sure how useful is the ScanNext metric as it is today. We can deprecate 
> it, and introduce a time based one to keep track of scan request latencies. 
> ps. Shamelessly using the parent jira (since these seem relavant). 



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