[
https://issues.apache.org/jira/browse/UIMA-4197?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Yu Lin updated UIMA-4197:
-------------------------
Description:
Hi, I'm doing research on asynchronous programming. I found at some places, the
code in uima-ducc ("trunk" branch) invokes "Future.get()" immediately after
starting a future task. Because "Future.get()" is a blocking call, the code
will block immediately.
For example, in "startAgents" method of "DuccAdmin" class (line 296), you
invoke "result.get()", where "result" is a Future, so the code blocks.
Why not use Guava ListenableFuture or Java8 CompletableFuture and avoid
"Future.get()"? These two new constructs provide callbacks to listen to the
Future's result:
http://docs.guava-libraries.googlecode.com/git/javadoc/com/google/common/util/concurrent/ListenableFuture.html
https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CompletableFuture.html
For example, in "DuccAdmin" class, you may put the code after "result.get()"
(such as lines 301-307) into "CompletableFuture.thenRunAsync" method.
Then make "startAgents" method return this CompletableFuture, and in the
callers (such as "DuccAdmin.process()" or "DuccAdmin.main" method) you can put
more continuations into "CompletableFuture.thenRunAsync". And you can also
invoke "Future.get" somewhere in the callers (for example in
"DuccAdmin.process()" method), instead of immediately.
Do you think such kind of change is correct and can improve the code?
was:
Hi, I'm doing research on asynchronous programming. I found at some places, the
code in uima-ducc ("trunk" branch) invokes "Future.get()" immediately after
starting a future task. Because "Future.get()" is a blocking call, the code
will block immediately.
For example, in "startAgents" method of "DuccAdmin" class (line 296), you
invoke "result.get()", where "result" is a Future, immediately after starting
future tasks, so the code blocks immediately. Such code has the same effect as
sequential code.
Why not use Guava ListenableFuture or Java8 CompletableFuture and avoid
"Future.get()"? These two new constructs provide callbacks to listen to the
Future's result:
http://docs.guava-libraries.googlecode.com/git/javadoc/com/google/common/util/concurrent/ListenableFuture.html
https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CompletableFuture.html
For example, in "DuccAdmin" class, you may put the code after "result.get()"
(such as lines 301-307) into "CompletableFuture.thenRunAsync" method.
Then make "startAgents" method return this CompletableFuture, and in the
callers (such as "DuccAdmin.process()" or "DuccAdmin.main" method) you can put
more continuations into "CompletableFuture.thenRunAsync". And you can also
invoke "Future.get" somewhere in the callers (for example in
"DuccAdmin.process()" method), instead of immediately.
Do you think such kind of change is correct and can improve the code?
> Using non-blocking "Future" instead of blocking "Future.get" to improve
> performance?
> ------------------------------------------------------------------------------------
>
> Key: UIMA-4197
> URL: https://issues.apache.org/jira/browse/UIMA-4197
> Project: UIMA
> Issue Type: Improvement
> Components: DUCC
> Reporter: Yu Lin
> Priority: Minor
>
> Hi, I'm doing research on asynchronous programming. I found at some places,
> the code in uima-ducc ("trunk" branch) invokes "Future.get()" immediately
> after starting a future task. Because "Future.get()" is a blocking call, the
> code will block immediately.
> For example, in "startAgents" method of "DuccAdmin" class (line 296), you
> invoke "result.get()", where "result" is a Future, so the code blocks.
> Why not use Guava ListenableFuture or Java8 CompletableFuture and avoid
> "Future.get()"? These two new constructs provide callbacks to listen to the
> Future's result:
> http://docs.guava-libraries.googlecode.com/git/javadoc/com/google/common/util/concurrent/ListenableFuture.html
> https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/CompletableFuture.html
> For example, in "DuccAdmin" class, you may put the code after "result.get()"
> (such as lines 301-307) into "CompletableFuture.thenRunAsync" method.
> Then make "startAgents" method return this CompletableFuture, and in the
> callers (such as "DuccAdmin.process()" or "DuccAdmin.main" method) you can
> put more continuations into "CompletableFuture.thenRunAsync". And you can
> also invoke "Future.get" somewhere in the callers (for example in
> "DuccAdmin.process()" method), instead of immediately.
> Do you think such kind of change is correct and can improve the code?
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
