[
https://issues.apache.org/jira/browse/HBASE-11544?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14327060#comment-14327060
]
Lars Hofhansl commented on HBASE-11544:
---------------------------------------
Excellent. Minor comments:
bq. When I changed the default value of caching to Integer.MAX_VALUE I was
running into OOME on the server since caching is used to presize the ArrayList
that holds results.
Meh :) Sorry I missed that when I did the simple change in HBASE-12976.
Yeah, simple solution is good. I'd actually like to change that size in all
branches now, even before we finish this. Any objections?
Quick note on small scans: They do not necessarily finish in one RPC. The
difference is that they do not hold any state on the server, which means each
RPC needs to re-setup the scanner stack, which is expensive, they also do
p-reads by default. But you're absolutely right, when need partial results you
sure-as-hell do not want to use a small scan.
This: "The setting of Scan#setMaxResultSize will now operate at the cell level
rather than the row level. " does not compute with this: "whereas the server
will only ever see partial Results for very large rows."
Is the limit per cell or per row?
> [Ergonomics] hbase.client.scanner.caching is dogged and will try to return
> batch even if it means OOME
> ------------------------------------------------------------------------------------------------------
>
> Key: HBASE-11544
> URL: https://issues.apache.org/jira/browse/HBASE-11544
> Project: HBase
> Issue Type: Bug
> Reporter: stack
> Assignee: Jonathan Lawlor
> Priority: Critical
> Labels: beginner
> Attachments: HBASE-11544-v1.patch
>
>
> Running some tests, I set hbase.client.scanner.caching=1000. Dataset has
> large cells. I kept OOME'ing.
> Serverside, we should measure how much we've accumulated and return to the
> client whatever we've gathered once we pass out a certain size threshold
> rather than keep accumulating till we OOME.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
