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https://issues.apache.org/jira/browse/HBASE-11724?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14095789#comment-14095789
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Jonathan Hsieh commented on HBASE-11724:
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{quote}
Isn't that all explained in the hbase-default doc?
A value of 0 or 1 indicate to use the same set of queues for gets and scans.
any other value is multiplied by the number of read queues that you have.
{quote}

I'm asking for a better explanation in the hbase-default.xml description -- if 
I were a user looking only at this file for how to set the value, I don't know 
if what valid values are. As worded "A value of 0 or 1 indicate to use the same 
set of queues for gets and scans." could be interpreted to mean that when I set 
the value to '0' queues are shared, and when I set the value to '1' the queues 
are also shared. It seems like could set it to 42 to turn off the get/scan 
sharing.  The fact that it is a float ratio between 0 and 1 is important to 
note here.

{quote}
Basically it does what you expect, "give me more scans" or "give me less scans" 
if you want to do the math to specify the right number of queues good for you, 
otherwise the will do what is right based on what you specified.
{quote}

if I just look at the hbase-default.xml I don't know what to expect.  I want to 
you make it clear for the user in the in hbase-default.xml

{quote}
aside the fact that I don't see validation in any place where we have conf 
values, here all the value that you set will result in a valid settings. < 0 
will result in 0, > 0 will result in 1
{quote}

where is this enforced?  I didn't see it in this patch and theese values get 
used in the calculations of # of counts.  As a user I could put values in like 
-1 or 42 and not know it was silly.

> Add to RWQueueRpcExecutor the ability to split get and scan handlers
> --------------------------------------------------------------------
>
>                 Key: HBASE-11724
>                 URL: https://issues.apache.org/jira/browse/HBASE-11724
>             Project: HBase
>          Issue Type: New Feature
>          Components: IPC/RPC
>            Reporter: Matteo Bertozzi
>            Assignee: Matteo Bertozzi
>            Priority: Minor
>             Fix For: 2.0.0
>
>         Attachments: HBASE-11724-v0.patch
>
>
> RWQueueRpcExecutor has the devision between reads and writes requests, but we 
> can split also small-reads and long-reads. This can be useful to force a 
> deprioritization of scans on the RS.



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