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https://issues.apache.org/jira/browse/HBASE-2937?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13036008#comment-13036008
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[email protected] commented on HBASE-2937:
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This seems like a bunch of functionality for a relatively small change. Nice
one Karthick. A few questions in the below.
src/main/java/org/apache/hadoop/hbase/HConstants.java
<https://reviews.apache.org/r/755/#comment1366>
Be careful about adding white space (no biggie)
src/main/java/org/apache/hadoop/hbase/client/HTable.java
<https://reviews.apache.org/r/755/#comment1367>
What if table is -ROOT-?
src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java
<https://reviews.apache.org/r/755/#comment1368>
Should this use the constant you added above? The deafault timeout?
src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java
<https://reviews.apache.org/r/755/#comment1369>
White space
src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java
<https://reviews.apache.org/r/755/#comment1370>
White space
src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java
<https://reviews.apache.org/r/755/#comment1371>
white space
src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java
<https://reviews.apache.org/r/755/#comment1372>
Will this work? What happens if lots of concurrent threads going against
lots of different tables each with a different timeout? Will a meta table call
pick up a short timeout that was put in place by a near-concurrent edit?
src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java
<https://reviews.apache.org/r/755/#comment1373>
Are there other exceptions you think we should rethrow? Connection
Exception?
- Michael
On 2011-05-18 23:56:26, Karthick Sankarachary wrote:
bq.
bq. -----------------------------------------------------------
bq. This is an automatically generated e-mail. To reply, visit:
bq. https://reviews.apache.org/r/755/
bq. -----------------------------------------------------------
bq.
bq. (Updated 2011-05-18 23:56:26)
bq.
bq.
bq. Review request for hbase.
bq.
bq.
bq. Summary
bq. -------
bq.
bq. Thanks to HBASE-3154, users now have the ability to specify a timeout for
client-side RPC calls. However, it doesn't go far enough in terms of how low
that timeout can go. Set the RPC timeout to too low a value and you run the
risk of timing out on calls to the meta tables, which are preconditions to
calling the {{HRegionInterface}} proxy.
bq.
bq. Given that, I believe the motivation at work in HBASE-2937 still hold
true. In this patch, I add a operation-level timeout, configurable through
"hbase.client.operation.timeout", which will override the value specified by
"hbase.rpc.timeout", if any, within the scope of the {{ServerCallable#call}}
method. In other words, the operation-level timeout does not apply to calls to
the meta tables.
bq.
bq. Furthermore, the patch treats an RPC timeout as a non-fatal event, in that
it will not cause the {{HBaseClient#Connection}} instance to be closed. Last
but not the least, users will also have the ability to set the operation
timeout on the {{HTable}} on the fly.
bq.
bq.
bq. This addresses bug HBASE-2937.
bq. https://issues.apache.org/jira/browse/HBASE-2937
bq.
bq.
bq. Diffs
bq. -----
bq.
bq. src/main/java/org/apache/hadoop/hbase/HConstants.java e9e3694
bq. src/main/java/org/apache/hadoop/hbase/client/HConnectionManager.java
b26f41e
bq. src/main/java/org/apache/hadoop/hbase/client/HTable.java 61e151a
bq. src/main/java/org/apache/hadoop/hbase/client/ServerCallable.java 6f22123
bq. src/main/java/org/apache/hadoop/hbase/ipc/HBaseClient.java 470e741
bq. src/main/java/org/apache/hadoop/hbase/ipc/HBaseRPC.java dbb57d9
bq. src/main/java/org/apache/hadoop/hbase/util/PoolMap.java 354d49a
bq.
bq. Diff: https://reviews.apache.org/r/755/diff
bq.
bq.
bq. Testing
bq. -------
bq.
bq. mvn test
bq.
bq.
bq. Thanks,
bq.
bq. Karthick
bq.
bq.
> Facilitate Timeouts In HBase Client
> -----------------------------------
>
> Key: HBASE-2937
> URL: https://issues.apache.org/jira/browse/HBASE-2937
> Project: HBase
> Issue Type: New Feature
> Components: client
> Affects Versions: 0.89.20100621
> Reporter: Karthick Sankarachary
> Assignee: Karthick Sankarachary
> Priority: Critical
> Fix For: 0.92.0
>
> Attachments: HBASE-2937.patch, HBASE-2937.patch
>
>
> Currently, there is no way to force an operation on the HBase client (viz.
> HTable) to time out if a certain amount of time has elapsed. In other words,
> all invocations on the HTable class are veritable blocking calls, which will
> not return until a response (successful or otherwise) is received.
> In general, there are two ways to handle timeouts: (a) call the operation in
> a separate thread, until it returns a response or the wait on the thread
> times out and (b) have the underlying socket unblock the operation if the
> read times out. The downside of the former approach is that it consumes more
> resources in terms of threads and callables.
> Here, we describe a way to specify and handle timeouts on the HTable client,
> which relies on the latter approach (i.e., socket timeouts). Right now, the
> HBaseClient sets the socket timeout to the value of the "ipc.ping.interval"
> parameter, which is also how long it waits before pinging the server in case
> of a failure. The goal is to allow clients to set that timeout on the fly
> through HTable. Rather than adding an optional timeout argument to every
> HTable operation, we chose to make it a property of HTable which effectively
> applies to every method that involves a remote operation.
> In order to propagate the timeout from HTable to HBaseClient, we replaced
> all occurrences of ServerCallable in HTable with an extension called
> ClientCallable, which sets the timeout on the region server interface, once
> it has been instantiated, through the HConnection object. The latter, in
> turn, asks HBaseRPC to pass that timeout to the corresponding Invoker, so
> that it may inject the timeout at the time the invocation is made on the
> region server proxy. Right before the request is sent to the server, we set
> the timeout specified by the client on the underlying socket.
> In conclusion, this patch will afford clients the option of performing an
> HBase operation until it completes or a specified timeout elapses. Note that
> a timeout of zero is interpreted as an infinite timeout.
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