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Date: Tue, 25 May 2010 09:53:34 -0700
Message-ID: <AANLkTikUzgPNm7UyCcHn1Sd0bJns21AJUiDqFs-EO5YF@mail.gmail.com>
Subject: Re: Why are writes faster than reads?
From: Tatu Saloranta <tsaloranta@gmail.com>
To: user@cassandra.apache.org
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On Tue, May 25, 2010 at 4:04 AM, Mark Greene <greenemj@gmail.com> wrote:
> I'm fairly certain the write path hits the commit log first, then the
> memtable.

True, but that does not make them any less sequential -- journal logs
are strictly sequential fast writes. Actual ordering occurs in memory,
and results are eventually flushed from memtable to disk.
There is no similar ordering for reads.

-+ Tatu +-