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From Anton Vinogradov <avinogra...@gridgain.com>
Subject Re: Changing public IgniteCompute API to improve changes in 5037 ticket
Date Tue, 25 Jul 2017 12:48:48 GMT
Alexei,

> How would task know the partition it is running over ?
Not sure it necessary.
You'll create pair partition-job at task's map phase.

> How can I assign task for each cache partition ?
Just implement map method generates map with size equals to partition count.

> How can I enforce partition reservation if task works with multiple
caches at once ?
This possible only in case caches use safe affinity function.
And it useful only it this case.

On Tue, Jul 25, 2017 at 3:22 PM, Alexei Scherbakov <
alexey.scherbakoff@gmail.com> wrote:

> Please read job instead task
>
> 2017-07-25 15:20 GMT+03:00 Alexei Scherbakov <alexey.scherbakoff@gmail.com
> >:
>
> > Main point of the issue is to provide clean API for working with
> > computations requiring data collocation
> >
> > affinityCall/Run provide the ability to run closure near data, but
> > map/reduce API is a way reacher: continuous mapping, task session, etc.
> >
> > As for proposed API, I do not understand fully how it solves the problem.
> >
> > Maxim, please provide detailed javadoc for each method and each argument
> > for presented API, and the answers to the following questions:
> >
> > 1. How would task know the partition it is running over ?
> >
> > 2. How can I assign task for each cache partition ?
> >
> > 3. How can I enforce partition reservation if task works with multiple
> > caches at once ?
> >
> >
> >
> >
> >
> > 2017-07-25 12:30 GMT+03:00 Anton Vinogradov <avinogradov@gridgain.com>:
> >
> >> Val,
> >>
> >> Sure, we can, but we'd like to use map/reduce without fearing that
> >> topology
> >> can change.
> >>
> >> On Mon, Jul 24, 2017 at 11:17 PM, Valentin Kulichenko <
> >> valentin.kulichenko@gmail.com> wrote:
> >>
> >> > Anton,
> >> >
> >> > You can call affinityCallAsync multiple times and then reduce locally.
> >> >
> >> > -Val
> >> >
> >> > On Mon, Jul 24, 2017 at 3:05 AM, Anton Vinogradov <
> >> > avinogradov@gridgain.com>
> >> > wrote:
> >> >
> >> > > Val,
> >> > >
> >> > > > What is the use case for which current affinityRun/Call API
> doesn't
> >> > work?
> >> > > It does not work for map/reduce.
> >> > >
> >> > > On Fri, Jul 21, 2017 at 11:42 PM, Valentin Kulichenko <
> >> > > valentin.kulichenko@gmail.com> wrote:
> >> > >
> >> > > > Maxim,
> >> > > >
> >> > > > The issue is that it's currently assumed to support job mapping,
> >> but it
> >> > > > actually doesn't. However, I agree that AffinityKeyMapped
> annotation
> >> > > > doesn't fit the use case well. Let's fix documentation and JavaDoc
> >> > then.
> >> > > >
> >> > > > As for the proposed API, it's overcomplicated, took me 15 minutes
> to
> >> > > > understand what it does :)
> >> > > >
> >> > > > What is the use case for which current affinityRun/Call API
> doesn't
> >> > work?
> >> > > >
> >> > > > -Val
> >> > > >
> >> > > > On Fri, Jul 21, 2017 at 5:57 AM, Kozlov Maxim <
> dreamx.max@gmail.com
> >> >
> >> > > > wrote:
> >> > > >
> >> > > > > Valentin,
> >> > > > >
> >> > > > > The author of tiket wants to see to provide some API allows
to
> map
> >> > > > > ComputeJobs to partitions or keys. If we use @AffinityKeyMapped
> >> then
> >> > > you
> >> > > > > need to enter the cache name parameter, I think this is
not
> >> > convenient
> >> > > > for
> >> > > > > the user. Therefore, I propose to extend the existing API.
> >> > > > > Having consulted with Anton V. decided to make a separate
> >> interface
> >> > > > > ReducibleTask, which will allow us to have different map
logic
> at
> >> > each
> >> > > > > inheritor.
> >> > > > >
> >> > > > > Old method, allows to map to node
> >> > > > > public interface ComputeTask<T, R> extends ReducibleTask<R>
{
> >> > > > >     @Nullable public Map<? extends ComputeJob, ClusterNode>
> >> > > > > map(List<ClusterNode> subgrid, @Nullable T arg) throws
> >> > IgniteException;
> >> > > > > }
> >> > > > >
> >> > > > > Brand new method with mapping to partitions, which solves
> topology
> >> > > change
> >> > > > > issues.
> >> > > > > public interface AffinityComputeTask<T, R> extends
> >> ReducibleTask<R> {
> >> > > > >     @Nullable public Map<? extends ComputeJob, Integer>
> >> > > > map(@NotnullString
> >> > > > > cacheName, List<Integer> partIds, @Nullable T arg)
throws
> >> > > > IgniteException;
> >> > > > > }
> >> > > > >
> >> > > > > public interface ReducibleTask<R> extends Serializable
{
> >> > > > >     public ComputeJobResultPolicy result(ComputeJobResult
res,
> >> > > > > List<ComputeJobResult> rcvd) throws IgniteException;
> >> > > > >
> >> > > > >     @Nullable public R reduce(List<ComputeJobResult>
results)
> >> throws
> >> > > > > IgniteException;
> >> > > > > }
> >> > > > >
> >> > > > > We also need to implement AffinityComputeTaskAdapter and
> >> > > > > AffinityComputeTaskSplitAdapter, for implementation by default.
> >> It
> >> > is
> >> > > > > right?
> >> > > > >
> >> > > > > In the IgniteCompute add:
> >> > > > >
> >> > > > > @IgniteAsyncSupported
> >> > > > > public <T, R> R affinityExecute(Class<? extends
> >> > AffinityComputeTask<T,
> >> > > > R>>
> >> > > > > taskCls, List<Integer> partIds, @Nullable T arg) throws
> >> > > IgniteException;
> >> > > > > @IgniteAsyncSupported
> >> > > > > public <T, R> R affinityExecute(AffinityComputeTask<T,
R> task,
> >> > > > > List<Integer> partIds, @Nullable T arg) throws IgniteException;
> >> > > > >
> >> > > > > public <T, R> ComputeTaskFuture<R> affinityExecuteAsync(Class<?
> >> > extends
> >> > > > > AffinityComputeTask<T, R>> taskCls, List<Integer>
partIds,
> >> @Nullable
> >> > T
> >> > > > arg)
> >> > > > > throws IgniteException;
> >> > > > > public <T, R> ComputeTaskFuture<R> affinityExecuteAsync(
> >> > > > AffinityComputeTask<T,
> >> > > > > R> task, List<Integer> partIds, @Nullable T arg)
throws
> >> > > IgniteException;
> >> > > > >
> >> > > > >
> >> > > > > How do you like this idea or do you insist that you need
to use
> >> > > > > @AffinityKeyMapped to solve the problem?
> >> > > > >
> >> > > > >
> >> > > > > > 13 июля 2017 г., в 6:36, Valentin Kulichenko
<
> >> > > > > valentin.kulichenko@gmail.com> написал(а):
> >> > > > > >
> >> > > > > > Hi Max,
> >> > > > > >
> >> > > > > > This ticket doesn't assume any API changes, it's about
broken
> >> > > > > > functionality. I would start with checking what tests
we have
> >> > > > > > for @AffinityKeyMapped and creating missing one. From
what I
> >> > > understand
> >> > > > > > functionality is broken completely or almost completely,
so I
> >> guess
> >> > > > > testing
> >> > > > > > coverage is very weak there.
> >> > > > > >
> >> > > > > > -Val
> >> > > > > >
> >> > > > > > On Wed, Jul 12, 2017 at 4:27 PM, Kozlov Maxim <
> >> > dreamx.max@gmail.com>
> >> > > > > wrote:
> >> > > > > >
> >> > > > > >> Igniters,
> >> > > > > >>
> >> > > > > >> jira: https://issues.apache.org/jira/browse/IGNITE-5037
<
> >> > > > > >> https://issues.apache.org/jira/browse/IGNITE-5037>
> >> > > > > >> How do you look to solve this ticket by adding
two methods to
> >> the
> >> > > > public
> >> > > > > >> IgniteCompute API?
> >> > > > > >>
> >> > > > > >> @IgniteAsyncSupported
> >> > > > > >> public void affinityRun(@NotNull Collection<String>
> cacheNames,
> >> > > > > >> Collection<Object> keys, IgniteRunnable job)
> >> > > > > >>    throws IgniteException;
> >> > > > > >>
> >> > > > > >> @IgniteAsyncSupported
> >> > > > > >> public <R> R affinityCall(@NotNull Collection<String>
> >> cacheNames,
> >> > > > > >> Collection<Object> keys, IgniteCallable<R>
job)
> >> > > > > >>    throws IgniteException;
> >> > > > > >>
> >> > > > > >> There is also a question of how to act when changing
the
> >> topology
> >> > > > during
> >> > > > > >> the execution of the job.
> >> > > > > >> 1) complete with an exception;
> >> > > > > >> 2) stop execution and wait until the topology is
rebuilt and
> >> > > continue
> >> > > > > >> execution;
> >> > > > > >>
> >> > > > > >> I think the second way, do you think?
> >> > > > > >>
> >> > > > > >> --
> >> > > > > >> Best Regards,
> >> > > > > >> Max K.
> >> > > > > >>
> >> > > > > >>
> >> > > > > >>
> >> > > > > >>
> >> > > > > >>
> >> > > > >
> >> > > > > --
> >> > > > > Best Regards,
> >> > > > > Max K.
> >> > > > >
> >> > > > >
> >> > > > >
> >> > > > >
> >> > > > >
> >> > > >
> >> > >
> >> >
> >>
> >
> >
> >
> > --
> >
> > Best regards,
> > Alexei Scherbakov
> >
>
>
>
> --
>
> Best regards,
> Alexei Scherbakov
>

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