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From Bhuvan Rawal <bhu1ra...@gmail.com>
Subject Re: High disk io read load
Date Sat, 18 Feb 2017 20:41:05 GMT
Hi Ben,

If its same on both machines then something else could be the issue. We
faced high disk io due to misconfigured read ahead which resulted in high
amount of disk io for comparatively insignificant network transfer.

Can you post output of blockdev --report for a normal node and 512 token
node.

Regards,

On Sun, Feb 19, 2017 at 2:07 AM, Benjamin Roth <benjamin.roth@jaumo.com>
wrote:

> cat /sys/block/sda/queue/read_ahead_kb
> => 8
>
> On all CS nodes. Is that what you mean?
>
> 2017-02-18 21:32 GMT+01:00 Bhuvan Rawal <bhu1rawal@gmail.com>:
>
>> Hi Benjamin,
>>
>> What is the disk read ahead on both nodes?
>>
>> Regards,
>> Bhuvan
>>
>> On Sun, Feb 19, 2017 at 1:58 AM, Benjamin Roth <benjamin.roth@jaumo.com>
>> wrote:
>>
>>> This is status of the largest KS of these both nodes:
>>> UN  10.23.71.10  437.91 GiB  512          49.1%
>>> 2679c3fa-347e-4845-bfc1-c4d0bc906576  RAC1
>>> UN  10.23.71.9   246.99 GiB  256          28.3%
>>> 2804ef8a-26c8-4d21-9e12-01e8b6644c2f  RAC1
>>>
>>> So roughly as expected.
>>>
>>> 2017-02-17 23:07 GMT+01:00 kurt greaves <kurt@instaclustr.com>:
>>>
>>>> what's the Owns % for the relevant keyspace from nodetool status?
>>>>
>>>
>>>
>>>
>>> --
>>> Benjamin Roth
>>> Prokurist
>>>
>>> Jaumo GmbH · www.jaumo.com
>>> Wehrstraße 46 · 73035 Göppingen · Germany
>>> Phone +49 7161 304880-6 <07161%203048806> · Fax +49 7161 304880-1
>>> <07161%203048801>
>>> AG Ulm · HRB 731058 · Managing Director: Jens Kammerer
>>>
>>
>>
>
>
> --
> Benjamin Roth
> Prokurist
>
> Jaumo GmbH · www.jaumo.com
> Wehrstraße 46 · 73035 Göppingen · Germany
> Phone +49 7161 304880-6 · Fax +49 7161 304880-1
> AG Ulm · HRB 731058 · Managing Director: Jens Kammerer
>

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