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From: Jonathan Ellis <jbellis@gmail.com>
Date: Sat, 20 Mar 2010 23:04:12 -0500
Message-ID: <e06563881003202104t341b0c99t6baec1a104b3c508@mail.gmail.com>
Subject: Re: why Cassandra 0.5.1 write speed is very slow
To: user@cassandra.apache.org
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If you're benchmarking throughput, then you absolutely have to be multithre=
aded.

2010/3/20 =B9=F9=C5=F4 <gpcuster@gmail.com>:
> You mean I waste lots of time waiting for the write reply?
>
> How could I avoid this problem? Using multi-thread for very write operati=
on?
>
> I am totally confused.
>
> Thx.
>
> =D4=DA 2010=C4=EA3=D4=C221=C8=D5 =C9=CF=CE=E711:16=A3=ACJonathan Ellis <j=
bellis@gmail.com>=D0=B4=B5=C0=A3=BA
>>
>> time a single-threaded client is spending waiting for a reply, is time
>> it's not spending sending another request
>>
>> 2010/3/20 =B9=F9=C5=F4 <gpcuster@gmail.com>:
>> > Good ideal, I will try it with client multithread write.
>> >
>> > But I don't understand the meaning of "d the latency in cluster mode
>> > hurts
>> > that much more."
>> >
>> > Thx.
>> >
>> > 2010/3/21 Jonathan Ellis <jbellis@gmail.com>
>> >>
>> >> 2010/3/20 =B9=F9=C5=F4 <gpcuster@gmail.com>:
>> >> > :)
>> >> >
>> >> > I just want to know why the write speed is ok in the standalone mod=
e
>> >> > but
>> >> > too
>> >> > slow in the cluster mode.
>> >> >
>> >> > Am I doing something wrong?
>> >>
>> >> Probably, but it's hard to say what.
>> >>
>> >> Maybe you're just not using enough threads in your benchmark and the
>> >> latency in cluster mode hurts that much more.
>> >
>> >
>> >
>> > --
>> > Regards
>> >    Peng Guo
>> >
>
>
>
> --
> Regards
>    Peng Guo
>