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From Laxmikant Upadhyay <laxmikant....@gmail.com>
Subject Re: write latency on single partition table
Date Sat, 07 Apr 2018 04:39:41 GMT
It seems your partition size is more..what is the size of value field ? Try
to keep your partition size within 100 mb.

On Sat, Apr 7, 2018, 9:45 AM onmstester onmstester <onmstester@zoho.com>
wrote:

>
> I've defained a table like this
>
> create table test (
> hours int,
> key1 int,
> value1 varchar,
> primary key (hours,key1)
> )
>
> For one hour every input would be written in single partition, because i
> need to group by some 500K records in the partition for a report with
> expected response time in less than 1 seconds so using key1 in partition
> key would made 500K partitions which would be slow on reads.
> Although using  this mechanism gains < 1 seconds response time on reads
> but the write delay increased surprisingly, for this table write latency
> reported by cfstats is more than 100ms but for other tables which accessing
> thousands of partitions while writing in 1 hour , the write delay is
> 0.02ms. But i was expecting that writes to test table be faster than other
> tables because always only one node and one partition would be accessed, so
> no memtable switch happens and all writes would be local to a single node?!
> Should i add another key to my partition key to distribute data on all of
> nodes?
>
> Sent using Zoho Mail <https://www.zoho.com/mail/>
>
>
>

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