Thanks everyone.
On Wed, 9 Aug 2023 at 01:00, Regis Le Bretonnic
wrote:
>
> Hi Surbhi
>
> We do use cassandra materialized views even if not recommended.
> There are known issues you have to make with. Despite of them, we still use
> VM.
> What we observe is :
> * there are inconsistency issue
Hi community
What is the expected P95 latency for Cassandra Read and Write queries
executed with Local_Quorum over a table with 3 replicas ? The queries are
done using the partition + clustering key and row size in bytes is not too
much, maybe 1-2 KB maximum.
Assuming CPU is not a crunch ?
We obs
Hi,
P95 should not be a problem if rightly designed. Levelled compaction
strategy further reduces this, however it consume some resources. For read,
caching is also helpful.
Can you check your cpu iowait as it could be the reason for delay
Regards,
Ashish
On Fri, 11 Aug, 2023, 04:58 Shaurya Gupta
Hi surbhi ,
There are 2 drawbacks associated with MV.
1. Inconsistent view
2. The lock it takes on the base table. This gets worse when you have huge
number of clustering keys in a specific partition.
It's better you re-design a seperate table and let your API do a parallel
write on both.
Regards
Though it's recommended to upgrade to latest version of 3.11.x and then to
ver 4 but even upgrading directly won't be a problem. Just check the
release notes.
However for production, I would recommend to go for 4.0.x latest stable
version.
Regards
Ashish
On Sat, 8 Jul, 2023, 05:44 Surbhi Gupta,
Thanks,
I am looking to to upgrade to 4.1.x .
Please advise.
Thanks
Surbhi
On Thu, Aug 10, 2023 at 5:39 PM MyWorld wrote:
> Though it's recommended to upgrade to latest version of 3.11.x and then to
> ver 4 but even upgrading directly won't be a problem. Just check the
> release notes.
>
> Ho
You can check in your lower environment.
On Fri, 11 Aug, 2023, 06:25 Surbhi Gupta, wrote:
> Thanks,
>
> I am looking to to upgrade to 4.1.x .
> Please advise.
>
> Thanks
> Surbhi
>
> On Thu, Aug 10, 2023 at 5:39 PM MyWorld wrote:
>
>> Though it's recommended to upgrade to latest version of 3.11
40ms is definitely higher than expected. Have you run your queries with TRACING enabled to see where the latency is coming from?https://docs.datastax.com/en/cql-oss/3.3/cql/cql_reference/cqlshTracing.html40ms is also a fairly specific duration: https://eklitzke.org/the-caveats-of-tcp-nodelay> On Li
The queries are rightly designed as I already explained. 40 ms is way too
high as compared to what I seen with other DBs and many a times with
Cassandra 3.x versions.
CPU consumed as I mentioned is not high, it is around 20%.
On Thu, Aug 10, 2023 at 5:14 PM MyWorld wrote:
> Hi,
> P95 should not
