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From "R. Verlangen" <ro...@us2.nl>
Subject Re: Writes slower then reads
Date Thu, 05 Jan 2012 11:07:05 GMT
CPU is idle (< 10% usage). Disk reads occasionally blocks over 32/64K.
Writes around 0-5MB per second. Network traffic 0.1 / 0.1 MB/s (in / out).
Paging 0. System int ~ 1300, csw ~ 2500.

2012/1/5 Philippe <watcherfr@gmail.com>

> What can you see in vmstat/dstat ?
> Le 5 janv. 2012 11:58, "R. Verlangen" <robin@us2.nl> a écrit :
>
> Hi there,
>>
>> I'm running a cassandra 0.8.6 cluster with 2 nodes (in 2 DC's), RF = 2.
>> Actual data on the nodes is only 1GB. Disk latency < 1ms. Disk throughput ~
>> 0.4MB/s. OS load always below 1 (on a 8 core machine with 16GB ram).
>>
>> When I'm running my writes against the cluster with cl = ONE all reads
>> appear to be faster then the writes.
>>
>> Average write speed = 1600us/operation
>> Average read speed = 200us/operation
>>
>> I'm really wondering why this is the case. Anyone got a clue?
>>
>> With kind regards,
>> Robin
>>
>

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