Based this  latest description, simply not specifying an affinity key here
would be sufficient.   But presumably you were specifying the affinity key
to cause co-location.   The reason a lookup on the K of the KV pair is fast
is because it can hash to a node.   If  the affinity key was not included
in the K then you would not get colocation.  To do a lookup on only part of
K means you cannot hash to node.    Assuming that you can't know the
affinity key a priori, i.e., you know the person and not the company, there
are other solutions.   Depending on the data, you may be able to use a
replicated cache for other (company) data rather than trying to co-locate
this record with that other data.  That increases the storage and
insert/update cost for company records.
There are also a number of solutions using Java to send closures to the
server nodes.

On Wed, Mar 21, 2018 at 1:55 AM, Naveen <[email protected]> wrote:

> My whole and sole requirement is to make lookup work fast, this can only be
> achieved with lookup based on primary key, cluster knows which node is
> holding this record based on the key, no other look-up can give best
> results
> close to primary key lookup.
>
> We have done some tests on lookup based on the indexed column, which is
> giving (1/5)th of the TPS of lookup based on the primary key
>
> Lookup with primary key was around 30K TPS
> Lookup on indexed column was around 6 K TPS
>
> Though its indexed, request still goes to all the nodes, instead of
> querying
> the source table it will query index table which is small in size and
> sorted, so retrieval process is faster, is this understanding correct ??
>
> Results are justifiable, considering the architecture, where indexes are
> distributed across the nodes.
>
> In my view, affinity should not influence the data model, at the most it
> can
> add  to the memory footprint by adding extra column to the table just for
> the same of using affinity (collocating the data).
>
> If the whole idea of having affinity key as part of the primary key is to
> just identify the order of fields, then we should look for other ways not
> by
> enforcing the affinity key as part of composite primary key.
>
> Regards
> Naveen
>
>
>
>
>
> --
> Sent from: http://apache-ignite-users.70518.x6.nabble.com/
>

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