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From "Hiller, Dean" <Dean.Hil...@nrel.gov>
Subject Re: Why so slow?
Date Mon, 20 Aug 2012 15:32:47 GMT
There is latency and throughput.  These are two totally different things even for MySQL.  If
you are single threaded, each request (even with MySql) has to be delayed by 1ms or whatever
your ping time is.  To fully utilize a 1Gps bandwidth, you NEED to be multithreaded or you
are wasting bandwidth…and even then, you probably waste bandwidth as one CPU can't always
keep up with keeping the pipe filled.

Later,
Dean

From: Peter Morris <mrpmorris@gmail.com<mailto:mrpmorris@gmail.com>>
Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>>
Date: Monday, August 20, 2012 9:29 AM
To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" <user@cassandra.apache.org<mailto:user@cassandra.apache.org>>
Subject: Re: Why so slow?

I'm assessing how quickly on average I can deal with a single request.  I cannot believe that
connecting through a 1Gbps network cable is 14 times slower.  I think I get a higher insert
rate for SQL Server.



On Mon, Aug 20, 2012 at 1:20 PM, Hiller, Dean <Dean.Hiller@nrel.gov<mailto:Dean.Hiller@nrel.gov>>
wrote:
 IF one has 1ms delay per request and the other has .001, 1000 requests will be a one second
delay tacked on(which is huge).  This is why he suggested multi-threaded ;).  Maybe there
is some other factors as well.

Dean

From: Peter Morris <mrpmorris@gmail.com<mailto:mrpmorris@gmail.com><mailto:mrpmorris@gmail.com<mailto:mrpmorris@gmail.com>>>
Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>"
<user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>>
Date: Monday, August 20, 2012 4:49 AM
To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>"
<user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>>
Subject: Re: Why so slow?

I've set NoDelay = true on the socket, and although it is much better it is still only giving
me 500 record inserts per second over a 1Gbps crossover cable - (I now also get 200 record
inserts per second over wireless.)

I would expect the cross over to have much better performance than this.  Any other ideas?




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