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From: Bongseo Jang [mailto:grayce...@gmail.com]
Sent: Friday, April 24, 2015 6:13 AM
To: user@cassandra.apache.org
Subject: Re: What is 'Read Reuqests' on OpsCenter exaclty?
I can see two numbers matches when the redundant selects are removed with 1
node
Let me try to reproduce your test and get back wiith some results.
Regards,
Carlos Juzarte Rolo
Cassandra Consultant
Pythian - Love your data
rolo@pythian | Twitter: cjrolo | Linkedin: *linkedin.com/in/carlosjuzarterolo
http://linkedin.com/in/carlosjuzarterolo*
Mobile: +31 6 159 61 814 | Tel:
You're quite right. I missed important thing first.
I found a mistake in my program while making test case. It turns out that
the original program has 3~4 selects for non-existing row keys plus a
select for existing row key. It was intended to do nothing but for next
tests. My original test
Carlos is right:
*Read Requests* - The number of read requests per second on the coordinator
nodes, analogous to client reads. Monitoring the number of requests over a
given time period reveals system read workload and usage patterns.
*Avg* - The average of values recorded during a time
Thanks a lot Carlos, Sebastian :-)
My test was with 1 node/1 replica settings, on which I assumed client
request = read request on the graph. Because there seems no read_repair and
already CL=ONE in my case, I need more explanation, don't I? Or can any
other internals be still involved?
Do you
Probably it takes in account the read repair, plus a read that have
consistency != 1 will produce reads on other machines (which are taken in
account). I don't know the internals of opscenter but I would assume that
this is the case.
If you want to test it further, disable read_repair, and make
