When cassandra-driver was executing the query, cassandra-driver returned error OperationTimedOut

Question

I use python script, that passes to cassandra batch query, like this: ``` query = 'BEGIN BATCH ' + 'insert into ... ; insert into ... ; insert into ...; ' + ' APPLY BATCH;' session.execute(query) ``` It is work some time, but in about 2 minutes after start scripts fails and print: ``` Traceback (most recent call last):
File "/home/fervid/Desktop/cassandra/scripts/parse_and_save_to_cassandra.cgi", line 127, in
session.execute(query)
File "/usr/local/lib/python2.7/dist-packages/cassandra/cluster.py", line 1103, in execute
result = future.result(timeout)
File "/usr/local/lib/python2.7/dist-packages/cassandra/cluster.py", line 2475, in result
raise OperationTimedOut(errors=self._errors, last_host=self._current_host)
cassandra.OperationTimedOut: errors={}, last_host=127.0.0.1

``` I changed timeout from `cassandra.yaml` to: read_request_timeout_in_ms: 15000 range_request_timeout_in_ms: 20000 write_request_timeout_in_ms: 20000 cas_contention…

Accepted Answer

This is a client side timeout (see the link in @Syrial's reply: http://datastax.github.io/python-driver/api/cassandra.html#cassandra.OperationTimedOut)

You can change the `Session` default timeout:

```
session = cluster.connect()
session.default_timeout = 30  # this is in *seconds*
```

You can change the timeout for a particular query:

```
session.execute(statement, 30, ...)
```

You could speed up the execution quite a bit by using prepared statements inside the `BATCH`. See the Batching statements sections in this post

If you are after even better results, please read these performance notes

When cassandra-driver was executing the query, cassandra-driver returned error OperationTimedOut

Solution

Problem