[jira] [Commented] (PHOENIX-4903) Hash cache RPC uses O(N) memory on master

["Josh Elser (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/PHOENIX-4903?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16613649#comment-16613649 ] 

Josh Elser commented on PHOENIX-4903:
-------------------------------------

{quote}To distribute the hash cache to region servers, the master node makes an `AddServerCacheRequest` RPC to each region servers
{quote}
The HMaster does this? I thought this was coordinated by the client. Or maybe the RS hosting system.catalog.

> Hash cache RPC uses O(N) memory on master
> -----------------------------------------
>
>                 Key: PHOENIX-4903
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-4903
>             Project: Phoenix
>          Issue Type: Improvement
>            Reporter: Marcell Ortutay
>            Priority: Major
>
> To distribute the hash cache to region servers, the master node makes an `AddServerCacheRequest` RPC to each region servers. If there are N region servers, it makes N of these RPC's. For each of the region servers, it generates a serialized RPC message and sends it out. This happens concurrently, and the result is that it uses O(N) memory on the master.
> As an example, if the `AddServerCacheRequest` RPC message is 100MB, and you have a cluster of 100 nodes, it would use 10GB memory on the master, potentially resulting in an "OutOfMemory" exception.
> It would be better if the master could use O(1) memory for the RPC.
> I observed this behavior in Phoenix 4.14.1



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)