Re: High latencies for simple queries

[Anishek Agarwal <an...@gmail.com>]

Hey all,

I was wondering if java driver has something like mentioned for python
driver above where it sleeps for 1 ms . My writes are very as as expected
with around 600 micro seconds per write instruction though read is bad at
1300 micro seconds.

Seems read latency is bad, is this expected ?

Thanks
Anishek

On Tue, Mar 31, 2015 at 9:11 PM, Tyler Hobbs <ty...@datastax.com> wrote:

> 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 <ty...@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 <be...@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 <ar...@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/>
>