From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Garzik <jeff@garzik.org>
Subject: Re: [tabled patch 1/1] fix the selection of chunk
Date: Tue, 25 May 2010 23:46:24 -0400
Message-ID: <4BFC9990.70309@garzik.org>
References: <20100525213041.53a1198e@redhat.com>
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To: Pete Zaitcev <zaitcev@redhat.com>
Cc: Project Hail List <hail-devel@vger.kernel.org>

On 05/25/2010 11:30 PM, Pete Zaitcev wrote:
> If a chunkserver goes down, tabled sometimes throws a phantom "object
> not found". It happens because we keep hitting the same down node and
> exhaust the retries. The existing code calls rand() every time and
> hopes for the best, but this is too likely to end poorly.
>
> The fix is to only randomize once before the retry loop, and then
> cycle through all available nodes deterministically. The same fix
> would apply even if we used a better technique to select an available
> chunkserver than just random.
>
> Also, we refactor the code just a little bit, so that the enormous
> function object_get_body gets somewhat easier to follow.
>
> Signed-off-by: Pete Zaitcev<zaitcev@redhat.com>

applied