incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Philip Shon <philip.s...@gmail.com>
Subject Re: Wide rows and reads
Date Thu, 05 Jul 2012 17:23:51 GMT
>From what I understand, wide rows have quite a bit of overhead, especially
if you are picking columns that are far apart from each other for a given
row.

This post by Aaron Morton was quite good at explaining this issue
http://thelastpickle.com/2011/07/04/Cassandra-Query-Plans/

-Phil

On Thu, Jul 5, 2012 at 12:17 PM, Oleg Dulin <oleg.dulin@gmail.com> wrote:

> Here is my flow:
>
> One process write a really wide row (250K+ supercolumns, each one with 5
> subcolumns, for the total of 1K or so per supercolumn)
>
> Second process comes in literally 2-3 seconds later and starts reading
> from it.
>
> My observation is that nothing good happens. It is ridiculously slow to
> read. It seems that if I wait long enough, the reads from that row will be
> much faster.
>
> Could someone enlighten me as to what exactly happens when I do this ?
>
> Regards,
> Oleg
>
>
>

Mime
View raw message