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From: tsuna <tsunanet@gmail.com>
Date: Tue, 1 Feb 2011 11:22:04 -0800
Message-ID: <AANLkTik++NyF02gQVPJuLMJ4pyxw0O2zoWiTqSNqRcyJ@mail.gmail.com>
Subject: Re: write performance degradation
To: dev@hbase.apache.org
Content-Type: text/plain; charset=ISO-8859-1

On Tue, Feb 1, 2011 at 7:40 AM, Ted Yu <yuzhihong@gmail.com> wrote:
> Thanks for the reminder.
>
> After adjusting swappiness to 2 on each node, I see:
> http://pastebin.com/tFcAj7rw
>
> Client buffer is now 10MB.
> But map tasks seem to be slower than before.

The output of vmstat doesn't show anything useful here, the machine is
100% idle up until the 3rd section where it's reading a bit from disk,
but it's still mostly idle.  Something else that we don't see from
this trace is amiss.

-- 
Benoit "tsuna" Sigoure
Software Engineer @ www.StumbleUpon.com