Re: Using K8s to Manage Cassandra in Production

[Павел Сапежко]

Hi, Hassaan! For example we are using C* in k8s in production for our video
surveillance system. Moreover, we are using Ceph RBD as our storage for
cassandra. Today we have 8 C* nodes each manages 2Tb of data.

On Fri, May 18, 2018 at 9:27 AM Hassaan Pasha  wrote:

> Hi,
>
> I am trying to craft a deployment strategy for deploying and maintaining a
> C* cluster. I was wondering if there are actual production deployments of
> C* using K8s as the orchestration layer.
>
> I have been given the impression that K8s managing a C* cluster can be a
> recipe for disaster, especially if you aren't well versed with the
> intricacies of a scale-up/down event. I know use cases where people are
> using Mesos or a custom tool built with terraform/chef etc to run their
> production clusters but have yet to find a real K8s use case.
>
> *Questions?*
> Is K8s a reasonable choice for managing a production C* cluster?
> Are there documented use cases for this?
>
> Any help would be greatly appreciated.
>
> --
> Regards,
>
>
> *Hassaan Pasha*
>
-- 

Regrads,

Pavel Sapezhko

Re: Understanding of cassandra metrics

[Павел Сапежко]

So, Range latency(or Scan in case of coordinator) appears only when we are
reading multiple partition key in the same query?

пт, 7 июл. 2017 г. в 20:29, Chris Lohfink <clohfin...@gmail.com>:

> The coordinator read/scan (Scan is just different naming for the Range, so
> coordinator view of RangeLatency) is the latencies from the coordinator
> perspective, so it includes network latency between replicas and such. This
> which is actually added for speculative retry (why there is no
> coordinatorWriteLatency). Only the CoordinatorReadLatency is used for it
> however.
>
> The Read/RangeLatency metrics are for local reads, basically just how long
> to read from disk and merge with sstables.
>
> The View* metrics are only relevant to materialized views. There actually
> is a partition lock for updates which ViewLockAcquireTime gives
> visibility too. Also there are sometimes reads required for updating
> materialized views, which ViewReadTime is for tracking. For more details id
> recommend
> https://opencredo.com/everything-need-know-cassandra-materialized-views/
>
> Chris
>
> On Fri, Jul 7, 2017 at 9:42 AM, ZAIDI, ASAD A <az1...@att.com> wrote:
>
>> What exactly does mean CoordinatorScanLatency for example
>>
>> CoordinatorScanLatency  is a timer metric that present coordinator range
>> scan latency for  table.
>>
>> Is it latency on full table scan or maybe range scan by clustering key?
>>
>> It is range scan.. clustering key is used to only store
>> data in sorted fashion – partition key along with chosen partitioner helps
>> in range scan of data.
>>
>> Can anybody write into partition while locked?
>>
>>     Writes are atomic – it depends on your chosen consistency
>> level to determine if writes will fail or succeed.
>>
>>
>>
>> *From:* Павел Сапежко [mailto:amelius0...@gmail.com]
>> *Sent:* Friday, July 07, 2017 8:23 AM
>> *To:* user@cassandra.apache.org
>> *Subject:* Re: Understanding of cassandra metrics
>>
>>
>>
>> Are you really think that I don't read docs? Do you have enough
>> information in the documentation? I think no. What exactly does mean 
>> CoordinatorScanLatency
>> for example? Is it latency on full table scan or maybe range scan by
>> clustering key? What exactly mean ViewLockAcquireTime? What is
>> "partition lock"? Can anybody write into partition while locked? Etc.
>>
>> пт, 7 июл. 2017 г. в 13:01, Ivan Iliev <ivan.iliev.il...@gmail.com>:
>>
>> 1st result on google returns:
>>
>>
>>
>> http://cassandra.apache.org/doc/latest/operating/metrics.html
>> <https://urldefense.proofpoint.com/v2/url?u=http-3A__cassandra.apache.org_doc_latest_operating_metrics.html=DwMFaQ=LFYZ-o9_HUMeMTSQicvjIg=FsmDztdsVuIKml8IDhdHdg=xLXSLhev337PLD18_DQUB610StqO2URoRumDH-UXdtk=xTDUr1_OtTvWNi15F4GNSYs6lzQHi-2wX7oa2T37RCY=>
>>
>>
>>
>> On Fri, Jul 7, 2017 at 12:16 PM, Павел Сапежко <amelius0...@gmail.com>
>> wrote:
>>
>> Hello, I have several question about cassandra metrics. What does exactly
>> mean the next metrics:
>>
>>- CoordinatorReadLatency
>>- CoordinatorScanLatency
>>- ReadLatency
>>- RangeLatency
>>- ViewLockAcquireTime
>>- ViewReadTime
>>
>> --
>>
>> С уважением,
>>
>> Павел Сапежко
>>
>> skype: p.sapezhko
>>
>>
>>
>> --
>>
>> С уважением,
>>
>> Павел Сапежко
>>
>> skype: p.sapezhko
>>
>
> --

С уважением,

Павел Сапежко

skype: p.sapezhko

Re: Understanding of cassandra metrics

[Павел Сапежко]

Are you really think that I don't read docs? Do you have enough information
in the documentation? I think no. What exactly does mean CoordinatorScanLatency
for example? Is it latency on full table scan or maybe range scan by
clustering key? What exactly mean ViewLockAcquireTime? What is "partition
lock"? Can anybody write into partition while locked? Etc.
пт, 7 июл. 2017 г. в 13:01, Ivan Iliev <ivan.iliev.il...@gmail.com>:

> 1st result on google returns:
>
> http://cassandra.apache.org/doc/latest/operating/metrics.html
>
> On Fri, Jul 7, 2017 at 12:16 PM, Павел Сапежко <amelius0...@gmail.com>
> wrote:
>
>> Hello, I have several question about cassandra metrics. What does exactly
>> mean the next metrics:
>>
>>- CoordinatorReadLatency
>>- CoordinatorScanLatency
>>- ReadLatency
>>- RangeLatency
>>    - ViewLockAcquireTime
>>- ViewReadTime
>>
>> --
>>
>> С уважением,
>>
>> Павел Сапежко
>>
>> skype: p.sapezhko
>>
>
> --

С уважением,

Павел Сапежко

skype: p.sapezhko

Understanding of cassandra metrics

[Павел Сапежко]

Hello, I have several question about cassandra metrics. What does exactly
mean the next metrics:

   - CoordinatorReadLatency
   - CoordinatorScanLatency
   - ReadLatency
   - RangeLatency
   - ViewLockAcquireTime
   - ViewReadTime

-- 

С уважением,

Павел Сапежко

skype: p.sapezhko