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From Abdul Patel <abd786...@gmail.com>
Subject Re: Cassandra limitations
Date Fri, 04 May 2018 18:39:28 GMT
Thanks ..
So whats ideal number when we should stop ..say 100 ?

On Friday, May 4, 2018, Jeff Jirsa <jjirsa@gmail.com> wrote:

> Cluster. The overhead is per cluster.
>
> There are two places you'll run into scaling pain here.
>
> 1) Size of the schema (which we have to serialize to send around) - too
> many tables, or too many columns in tables, can cause serializing schema to
> get really expensive and cause problems
> 2) Too many memtables - assume that all of them will have some tiny
> trivial amount of data in them, maybe 1MB. 200 * 1MB = 200MB of heap just
> for empty memtables. If you have a thousand tables, that's a gigabyte of
> heap, just for EMPTY memtables.
>
>
>
>
>
> On Fri, May 4, 2018 at 11:17 AM, Abdul Patel <abd786.ap@gmail.com> wrote:
>
>> I have 3 projects in pipeline adding 3 different cluster  across all
>> environwments would too costly option :)
>>
>> So 200 tables per keyspace or per cluster?
>>
>>
>> On Friday, May 4, 2018, Durity, Sean R <SEAN_R_DURITY@homedepot.com>
>> wrote:
>>
>>> The issue is more with the number of tables, not the number of
>>> keyspaces. Because each table has a memTable, there is a practical limit to
>>> the number of memtables that a node can hold in its memory. (And scaling
>>> out doesn’t help, because every node still has a memTable for every table.)
>>> The practical table limit I have heard is in the low hundreds – maybe 200
>>> as a rough estimate.
>>>
>>>
>>>
>>> In general, we create a new cluster (instead of a new keyspace) for each
>>> application.
>>>
>>>
>>>
>>>
>>>
>>> Sean Durity
>>>
>>> *From:* Abdul Patel <abd786.ap@gmail.com>
>>> *Sent:* Thursday, May 03, 2018 5:56 PM
>>> *To:* User@cassandra.apache.org
>>> *Subject:* [EXTERNAL] Cassandra limitations
>>>
>>>
>>>
>>> Hi ,
>>>
>>>
>>>
>>> In my environment, we are coming up with 3 to 4 new projects , hence new
>>> keyspaces will be coming into picture.
>>>
>>> Do we have any limitations or performance issues when we hit to a number
>>> of keyspaces or number of nodes vs keyspaces?
>>>
>>> Also connections limitations if any?
>>>
>>>
>>>
>>> I know as data grows we can add more nodes and memory but nor sure about
>>> somethinh else which need to take into consideration.
>>>
>>>
>>>
>>>
>>>
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