Hi Alex,
I don't see any attached image. Can you please send it one more time?
Best wishes,
Pavel
On 16 November 2017 at 01:04, Alex Circus <circus.alexan...@gmail.com>
wrote:
> Hi,
>
> *On short:*
> I use cassandra 3.0.9 in a cluster of 6 nodes.
> 1. I create a keyspace called test:
> CREATE KEYSPACE business WITH replication = {'class':
> 'SimpleStrategy', 'replication_factor': '3'} AND durable_writes = true;
> 2. I create table called test:
>
> CREATE TABLE test.test (
>
> test_id bigint,
>
> test_value text
>
> PRIMARY KEY (test_id)
>
> )
>
> 3. I insert test_id=23 and test_value=some very large string/html (like
> 406088 chars utf8).
>
> 4. I query for test_id=35 and I get timeout (even with clqsh
> --request-timeout=3600).......
>
> 5. If I run the above on an existing cassandra cluster with cassa 2.0 the
> select returns instantly....The Java heap size is 8GB and in JMX I see max
> 4GB used of these 8 GB in the new cluster....
>
>
> *Detailed:*
>
> The above was just a test. The real scenario is:
>
> I migrated some tables from an old cassa (2.0) cluster with 9 nodes into
> another with 6 nodes and with cassa 3.0.9 and there was a lot of
> problems....
>
> I have a table like this:
>
> CREATE TABLE table (
> id text,
> ts text,
> score decimal,
> type text,
> values text,
> PRIMARY KEY (id, ts)
> ) WITH CLUSTERING ORDER BY (ts DESC)
>
> and the following query (which returns instantly):
>
> SELECT * FROM keyspace.table WHERE id='someId' AND ts IN
> ('2017-10-15','2017-10-16','2017-10-17','2017-10-18','2017-10-19','2017-10-20','2017-10-21','2017-10-22','2017-10-23','2017-10-24','2017-10-25','2017-10-26','2017-10-27','2017-10-28','2017-10-29','2017-10-30','2017-10-31','2017-11-01','2017-11-02','2017-11-03','2017-11-04','2017-11-05','2017-11-06');
>
> *If I add another day in the IN clause, the response never comes (even
> after 10 minutes!!!):*
>
> SELECT * FROM keyspace.table WHERE id='someId' AND ts IN
> ('2017-10-15','2017-10-16','2017-10-17','2017-10-18','
> 2017-10-19','2017-10-20','2017-10-21','2017-10-22','
> 2017-10-23','2017-10-24','2017-10-25','2017-10-26','
> 2017-10-27','2017-10-28','2017-10-29','2017-10-30','
> 2017-10-31','2017-11-01','2017-11-02','2017-11-03','
> 2017-11-04','2017-11-05','2017-11-06', *'2017-11-07'*);
>
> *The 'values' column may have large json data. *
>
> I managed to trace one of the timeouts by looking into system_trace
> keyspace. Please look into the attached image and see the last process took
> 10 minutes!!!
>
> I think there is some size limit somewhere because in* the IN clause *if
> I have 23 params it works(under 1 second), but with more(1+) it fails. The
> rows are the same size (same json size on all). In node2 of those 6 it
> works with 24 params. In node1 and node3 no. The other nodes I haven't
> checked yet.
>
> I saw no concluding logs except this one from cassa's debug.log (in the
> moment of the timeout or very close to that):
>
> *DEBUG [Thrift:2608] 2017-11-15 13:48:05,611 ReadCallback.java:126 - Timed
> out; received 0 of 1 responses*
>
> I think this problem has the same root cause as the one from the test
> (large html text) and it is related to some memory limit by code somewhere.
>
>
> Thank you,
>
> Alex.
> [image: screenshot.png]
>
>
