Hi,

We are running apache ignite 2.11 with cache configuration FULL_SYNC and
REPLICATED mode.

Our use case is :

1. *Multiple thin clients are adding data* into a cache using putAll
operation.
2. *Simultaneously the server is reading the data* using server cache
iterator.
3. *While iterating over the cache, data is removed from the cache and
added into new cache using a transaction*, i.e. transaction with remove and
put operations. We have transaction *concurrency - pessimistic and
isolation levels - repeatable_read*.

But we are seeing few missing entries at server side, i.e. server is not
able to read all the data put by client. E.g. in one of the run, all thin
clients put 5000 entries, server is able to read only 4999 entries. Here we
saw 1 entry was not read by server.

*Another observation is that, if we remove the transaction in the second
step above, or use optimistic transaction with serializable isolation
level, then this issue is not observed*.

What could be the possible problem in this use case
with pessimistic concurrency and repeatable_read isolation level? This is
particularly important as this configuration is resulting in data loss.

-- 
Regards,
Sumit Deshinge

Reply via email to