[MDEPLOY-206] Support parallel deployment for deployAtEnd

[slawekjaranowski]

Each whole module will be deployed by resolver in one thread.
We have parallel deployment on module level.

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[gnodet]

@slawekjaranowski the code for multi-threaded deploy should work if the number of threads is set to 1. Should we just use a single code path for both ?

[gnodet]

@slawekjaranowski the code for multi-threaded deploy should work if the number of threads is set to 1. Should we just use a single code path for both ?

In case we really want to avoid creating a thread pool with 1 thread, we could use https://guava.dev/releases/19.0/api/docs/com/google/common/util/concurrent/MoreExecutors.html#newDirectExecutorService() ...

[slawekjaranowski]

There are two code paths:

• number of threads <= 1 - collect all artifacts from all module and call in one request for Resolver
• number of threads > 1 - create thread pool and create separate deploy request per module

[slawekjaranowski]

@gnodet Is my answer sufficient for you?

[gnodet]

@gnodet Is my answer sufficient for you?

Yes, though, due to the locking that happens inside the resolver, I wonder if it would make more sense to have this parallel upload done inside the resolver rather than in the deploy plugin. @cstamas ?

[slawekjaranowski]

Yes, though, due to the locking that happens inside the resolver, I wonder if it would make more sense to have this parallel upload done inside the resolver rather than in the deploy plugin.

That is the reason that I execute deploy for whole module in separate thread - we have the same situation like executing Maven with -T, each module will be deployed in own thread.

[mattnelson]

sorry for the late review.

Would it be possible to support dynamic syntax like is done with the CLI parallelism flag -T 1C that way the deploy threads could scale with the hardware without being tightly coupled to config.

[slawekjaranowski]

Can be ... 😄

[cstamas]

@gnodet Is my answer sufficient for you?

Yes, though, due to the locking that happens inside the resolver, I wonder if it would make more sense to have this parallel upload done inside the resolver rather than in the deploy plugin. @cstamas ?

See https://issues.apache.org/jira/browse/MRESOLVER-32?focusedCommentId=17607557&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-17607557

And I agree, this should be better solved in resolver (would be nicer at least). IMO this plugin should simply create 1 deploy request and lump it onto resolver to "solve it".

[jira-importer]

Resolve #480