If I'm reading this correctly, what you are seeing is the read_timeout on
Cassandra side and not the client side timeout. Even if you set the client
side timeouts, the C* read & write timeouts are still respected on that
side.
On Mon, Jun 2, 2014 at 10:55 AM, Marcelo Elias Del Valle <
marc...@s1mbi0se.com.br> wrote:
> I am using Cassandra 2.0 with python CQL.
>
> I have created a column family as follows:
>
> CREATE KEYSPACE IF NOT EXISTS Identification
> WITH REPLICATION = { 'class' : 'NetworkTopologyStrategy',
> 'DC1' : 1 };
>
> USE Identification;
>
> CREATE TABLE IF NOT EXISTS entitylookup (
> name varchar,
> value varchar,
> entity_id uuid,
> PRIMARY KEY ((name, value), entity_id))
> WITH
> caching=all;
>
> I then try to count the number of records in this CF as follows:
>
> #!/usr/bin/env pythonimport argparseimport sysimport tracebackfrom cassandra
> import ConsistencyLevelfrom cassandra.cluster import Clusterfrom
> cassandra.query import SimpleStatement
> def count(host, cf):
> keyspace = "identification"
> cluster = Cluster([host], port=9042, control_connection_timeout=600000000)
> session = cluster.connect(keyspace)
> session.default_timeout=600000000
>
> st = SimpleStatement("SELECT count(*) FROM %s" % cf,
> consistency_level=ConsistencyLevel.ALL)
> for row in session.execute(st, timeout=600000000):
> print "count for cf %s = %s " % (cf, str(row))
> dump_pool.close()
> dump_pool.join()
> if __name__ == "__main__":
> parser = argparse.ArgumentParser()
> parser.add_argument("-cf", "--column-family", default="entitylookup",
> help="Column Family to query")
> parser.add_argument("-H", "--host", default="localhost", help="Cassandra
> host")
> args = parser.parse_args()
>
> count(args.host, args.column_family)
>
> print "fim"
>
> The count is not that useful to me, it's just a test with an operation
> that takes long to complete.
>
> Although I have defined timeout as 600000000 seconds, after less than 30
> seconds I get the following error:
>
> ./count_entity_lookup.py -H localhost -cf entitylookup
> Traceback (most recent call last):
> File "./count_entity_lookup.py", line 27, in <module>
> count(args.host, args.column_family)
> File "./count_entity_lookup.py", line 16, in count
> for row in session.execute(st, timeout=None):
> File
> "/home/mvalle/pyenv0/local/lib/python2.7/site-packages/cassandra/cluster.py",
> line 1026, in execute
> result = future.result(timeout)
> File
> "/home/mvalle/pyenv0/local/lib/python2.7/site-packages/cassandra/cluster.py",
> line 2300, in result
> raise self._final_exception
> cassandra.ReadTimeout: code=1200 [Timeout during read request]
> message="Operation timed out - received only 1 responses."
> info={'received_responses': 1, 'data_retrieved': True, 'required_responses':
> 2, 'consistency': 5}
>
> It seems the answer was found in just a replica, but this really doesn't
> make sense to me. Should't cassandra be able to query it anyway?
>
> These tests are running in a two node cluster, with RF = 2, write and read
> consistency = ALL (but same results using QUORUM).
>
> Thanks in advance.
>
> Best regards,
>
> Marcelo.
>
--
:- a)
Alex Popescu
Sen. Product Manager @ DataStax
@al3xandru
