From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <f3a044b2e13339d9f22c5aeb43cc9aa2@swtch.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] Clearing venti arena during install
From: "Russ Cox" <rsc@swtch.com>
Date: Sun, 26 Mar 2006 19:09:15 -0500
In-Reply-To: <20060326210445.19843295CD@mail.bitblocks.com>
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> If fossil+venti is chosen during installation, the entire
> venti arena partition is cleared.  Is there a way to avoid
> clearing all of the arena space?  Since in a sense it is an
> append only log, and the purpose for clearing it is,
> presumably, to allow recreating the index, may be a shortcut
> exists?  Doing so will save a lot of time and space
> particularly on a qemu VM.  In qemu one can use a sparse file
> or a qcow format file which allocates space only for data
> actually written.  Writing even zeroes can eat up space.

Any sparse file worth its salt would catch the case
where you write zeros to a hole and not do anything.

That said, I'd rather leave the zeroing in for now.
The new venti, which I am testing on Plan 9 right now,
does not require the zeroing.

Russ