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https://issues.apache.org/jira/browse/HBASE-17449?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15818020#comment-15818020
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Phil Yang edited comment on HBASE-17449 at 1/11/17 11:16 AM:
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Timeout for scan is complex after we having heartbeat in 1.1+. As long as
server can responds an heartbeat in time, ResultScanner.next() will always be
blocked until we can get a Result to users. So setting scan timeout is only to
prevent server not responding, while operation timeout can limit the max
blocking time for all the other operations. I think AsyncTable's scan is same
that we may take a long time before we call ScanResultConsumer.onNext or
ResultScanner.next() or RawScanResultConsumer.onNext()? [~Apache9]
+1 for using a new key for scan rpc timeout because now it use same key with
scanner TTL at server which confuse users.
For read/write timeout, as I said, we need to write in doc what is the timeout
for batch/append/increment.
was (Author: yangzhe1991):
Timeout for scan is complex after we having heartbeat in 1.1+. As long as
server can responds an heartbeat in time, ResultScanner.next() will always be
blocked until we can get a Result to users. So setting scan timeout is only to
prevent server not responding, while operation timeout can limit the max
blocking time for all the other operations.
+1 for using a new key for scan rpc timeout because now it use same key with
scanner TTL at server which confuse users.
For read/write timeout, as I said, we need to write in doc what is the timeout
for batch/append/increment.
> Add explicit document on different timeout settings
> ---------------------------------------------------
>
> Key: HBASE-17449
> URL: https://issues.apache.org/jira/browse/HBASE-17449
> Project: HBase
> Issue Type: Improvement
> Components: documentation
> Reporter: Yu Li
>
> Currently we have more than one timeout settings, mainly includes:
> * hbase.rpc.timeout
> * hbase.client.operation.timeout
> * hbase.client.scanner.timeout.period
> And in latest branch-1 or master branch code, we will have two other
> properties:
> * hbase.rpc.read.timeout
> * hbase.rpc.write.timeout
> However, in current refguid we don't have explicit instruction on the
> difference of these timeout settings (there're explanations for each
> property, but no instruction on when to use which)
> In my understanding, for RPC layer timeout, or say each rpc call:
> * Scan (openScanner/next): controlled by hbase.client.scanner.timeout.period
> * Other operations:
> 1. For released versions: controlled by hbase.rpc.timeout
> 2. For 1.4+ versions: read operation controlled by hbase.rpc.read.timeout,
> write operation controlled by hbase.rpc.write.timeout, or hbase.rpc.timeout
> if the previous two are not set.
> And hbase.client.operation.timeout is a higher-level control counting retry
> in, or say the overall control for one user call.
> After this JIRA, I hope when users ask questions like "What settings I should
> use if I don't want to wait for more than 1 second for a single
> put/get/scan.next call", we could give a neat answer.
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