Could you please share your configuration files, cache configurations, logs
from all nodes and the code snippets you use to do the queries (visor
commands, SQL, etc)?


Bellenger, Dominique wrote
> Hey Igniters,
> I've the following setup (Ignite .NET 2.4): 2 Server nodes, 1 client node
> doing SQL-queries on the cache periodically (every 20 Seconds in my case).
> The cache is filled with 110_000 entries from a database, using
> "LoadCache" method. Key is a string representation of a number, nothing
> fancy here.
> Situation: Both server nodes are put under pressure by doing affinity-run
> compute jobs on both nodes, affecting all cache entries (read, change, put
> every entry).
> I made the following observations:
>   1.  Visorcmd showed that the entries were distributed like 60_000 on one
> node and 34_000 on the other. The same sum (94_000) was shown on the
> client side on every periodic "tick" when calling "GetSize" on the cache
> instance
> (https://github.com/apache/ignite/blob/master/modules/platforms/dotnet/Apache.Ignite.Core/Cache/ICache.cs#L685).
>      *   Why are there entries missing? Running SELECT Count(*) on the
> Cache with SQLLine reports back 110_000 entries.
>      *   Why are the entries not distributed 50/50 (or nearly 50/50)?
>   1.  On the client, the SQL query invoked on every "tick" returned
> sometimes 110_000 entries, sometimes 60_000 or 34_000. There was no error
> or warning in the client or server log about failing SQL queries.
>      *   In a partitioned cache both servers do a query and the results
> are merged, if I understood correctly. It seems to me that one of the
> servers sometimes returns an empty result set and therefore the client
> gets a too small result set. Question is: why does this happen even
> without a warning on the server nodes about a failing query?
>   2.  In that situation the client is not able to load a specific entry
> from the cache multiple times using TryGet(TK key, out TV value)
> (https://github.com/apache/ignite/blob/master/modules/platforms/dotnet/Apache.Ignite.Core/Cache/ICache.cs#L297).
> Those entries definitely are existing in the cache.
>   3.  In that situation on one of both server nodes I get errors that an
> entry could not be loaded (like in 3) but on the affinity-server node!).
> In my understanding the compute jobs shall get executed on the primary
> node for the given key. And this node is not able to load an entry by that
> key (when under heavy CPU pressure)?
> Something is strange here. Any ideas?
> Cheers,
> Dome

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