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Date: Wed, 6 Feb 2019 13:52:44 +0300
From: Vladimir Davydov <vdavydov.dev@gmail.com>
Subject: Re: [tarantool-patches] Re: [PATCH 7/9] vinyl: randomize range
 compaction to avoid IO load spikes
Message-ID: <20190206105244.c4gkhb3xsn2pkqmp@esperanza>
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To: Konstantin Osipov <kostja@tarantool.org>
Cc: tarantool-patches@freelists.org
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On Wed, Feb 06, 2019 at 01:44:19PM +0300, Konstantin Osipov wrote:
> * Vladimir Davydov <vdavydov.dev@gmail.com> [19/02/06 13:31]:
> > Over how many dumps? What do we do after restart, when there's no
> > history and perhaps even no level 1?
> 
> A am thinking about something along these lines: 
> f(n+1) = (f(n) + x*k)(1+k) - where k is the weight used to scale
> the next input

What should be k equal to?

Also, what we should do after restart when there's no history?

Why is using the last level size as reference bad?

> 
> alternatively:
> 
> f(n+1) = sqrt((f(n)^2 + x^2)/2)