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From Tyler Hobbs <ty...@datastax.com>
Subject Re: High latencies for simple queries
Date Tue, 31 Mar 2015 15:41:18 GMT
To clarify, that's in Cassandra 2.1+.  In 2.0 and earlier, we used
http://code.google.com/a/apache-extras.org/p/cassandra-dbapi2/ for cqlsh.

On Tue, Mar 31, 2015 at 10:40 AM, Tyler Hobbs <tyler@datastax.com> wrote:

> The python driver that we bundle with Cassandra for cqlsh is the normal
> python driver (https://github.com/datastax/python-driver), although
> sometimes it's patched for bugfixes or is not an official release.
>
> On Sat, Mar 28, 2015 at 5:36 PM, Ben Bromhead <ben@instaclustr.com> wrote:
>
>> cqlsh runs on the internal cassandra python drivers: cassandra-pylib and
>> cqlshlib.
>>
>> I would not recommend using them at all (nothing wrong with them, they
>> are just not built with external users in mind).
>>
>> I have never used python-driver in anger so I can't comment on whether it
>> is genuinely slower than the internal C* python driver, but this might be a
>> question for python-driver folk.
>>
>> On 28 March 2015 at 00:34, Artur Siekielski <artc@vhex.net> wrote:
>>
>>> On 03/28/2015 12:13 AM, Ben Bromhead wrote:
>>>
>>>> One other thing to keep in mind / check is that doing these tests
>>>> locally the cassandra driver will connect using the network stack,
>>>> whereas postgres supports local connections over a unix domain socket
>>>> (this is also enabled by default).
>>>>
>>>> Unix domain sockets are significantly faster than tcp as you don't have
>>>> a network stack to traverse. I think any driver using libpq will attempt
>>>> to use the domain socket when connecting locally.
>>>>
>>>
>>> Good catch. I assured that psycopg2 connects through a TCP socket and
>>> the numbers increased by about 20%, but it still is an order of magnitude
>>> faster than Cassandra.
>>>
>>>
>>>> But I'm going to hazard a guess something else is going on with the
>>>> Cassandra connection as I'm able to get 0.5ms queries locally and that's
>>>> even with trace turned on.
>>>>
>>>
>>> Using python-driver?
>>>
>>
>>
>>
>> --
>>
>> Ben Bromhead
>>
>> Instaclustr | www.instaclustr.com | @instaclustr
>> <http://twitter.com/instaclustr> | (650) 284 9692
>>
>
>
>
> --
> Tyler Hobbs
> DataStax <http://datastax.com/>
>



-- 
Tyler Hobbs
DataStax <http://datastax.com/>

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