ignite-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Nikolai Tikhonov <ntikho...@apache.org>
Subject Re: Can a Continuous Queries miss some updates order?
Date Fri, 31 Mar 2017 14:16:27 GMT

Continuous Query (CQ) garanties that the order for events will be preserved
per entry. For example:

cache.put(key1, 100);
cache.put(key2, 100);
cache.put(key1, 200);
cache.put(key2, 200);

CQ guarantees that for key1 events will be received in the following order
(1, 100) --> (1, 200) but you can got event for key2 early than for key1.
Ignite doesn't have limitation on count of caches and CQ.

On Fri, Mar 31, 2017 at 4:57 PM, ctranxuan <cedric.tranxuan@streamdata.io>

> Hi,
> We are testing Apache Ignite Continuous Queries and during the tests, we
> have noticed that some continuous queries misses some updates of the cache.
> Our use case is the following one:
> - we have a feeder (that is part of the server nodes) and that feeds 1000
> caches with data every seconds
> - we have a client program (that is part of the server nodes) that opens
> 1000 continuous queries, 1 continuous query per cache
> So, some of these continuous queries gets from times to times few updates
> of
> the cache in the wrong order (i.e. in an order that is different from the
> order the items have been pushed in the cache). We were wondering whether
> the fact that a continuous query gets updates of the cache in a wrong order
> was "normal".
> We have also performed the test with 500, 250, 100 caches and have the same
> results.
> Besides, we are also wondering how many caches and continuous queries can
> be
> created? Does Apache Ignite support hundred thousands of creation of caches
> and continuous queries?
> The code for the tests can be found there:
> https://github.com/ctranxuan/ignite-cq-bench-parent
> We use Ignite 1.9.0.
> Thanks in advance for the answers!
> --
> View this message in context: http://apache-ignite-users.
> 70518.x6.nabble.com/Can-a-Continuous-Queries-miss-some-
> updates-order-tp11620.html
> Sent from the Apache Ignite Users mailing list archive at Nabble.com.

View raw message