From: ching <lsching17@gmail.com>
To: Hugo Mills <hugo@carfax.org.uk>,
"linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>
Cc: cwillu <cwillu@cwillu.com>, Felix Pepinghege <postfach@pepinghege.net>
Subject: Re: Why btrfs inline small file by default?
Date: Thu, 01 Nov 2012 05:07:03 +0800 [thread overview]
Message-ID: <509192F7.5040807@gmail.com> (raw)
In-Reply-To: <20121031001203.GD3102@twin.jikos.cz>
On 10/31/2012 08:12 AM, David Sterba wrote:
> On Wed, Oct 31, 2012 at 07:47:14AM +0800, ching wrote:
>> On 10/31/2012 06:19 AM, Hugo Mills wrote:
>>> On Tue, Oct 30, 2012 at 10:14:12PM +0000, Hugo Mills wrote:
>>>>> if i have 10G small files in total, then it will consume 20G by default.
>>>> If those small files are each 128 bytes in size, then you have
>>>> approximately 80 million of them, and they'd take up 80 million pages,
>>>> or 320 GiB of total disk space.
>>> Sorry, to make that clear -- I meant if they were stored in Data.
>>> If they're inlined in metadata, then they'll take approximately 20 GiB
>>> as you claim, which is a lot less than the 320 GiB they'd be if
>>> they're not.
>>>
>> is it the same for:
>> 1. 3k per file with leaf size=4K
>> 2. 60k per file with leaf size=64k
> The inline limit is minimum of
> * 'max_inline' (8k by default)
> * PAGE_SIZE
> * leafsize - header
>
> so 60k files for 64k leaves will not get inlined, unless you have a
> system with 64k pages.
>
thank you very much for your clear explanation :)
this is the first time i heard about this.
ching
next prev parent reply other threads:[~2012-10-31 21:07 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-30 11:04 Why btrfs inline small file by default? ching
2012-10-30 12:04 ` Felix Pepinghege
2012-10-30 12:17 ` cwillu
2012-10-30 21:40 ` ching
2012-10-30 22:14 ` Hugo Mills
2012-10-30 22:19 ` Hugo Mills
2012-10-30 23:47 ` ching
2012-10-31 0:12 ` David Sterba
2012-10-31 21:07 ` ching [this message]
2012-10-31 0:18 ` cwillu
2012-10-31 8:48 ` Ahmet Inan
2012-10-31 9:39 ` cwillu
2012-10-31 10:48 ` Ahmet Inan
2012-10-31 10:55 ` Michael Kjörling
2012-10-31 11:10 ` Ahmet Inan
2012-10-31 10:57 ` cwillu
2012-10-31 11:56 ` Michael Kjörling
2012-10-31 13:27 ` Ahmet Inan
2012-10-31 13:44 ` Roman Mamedov
2012-10-31 21:05 ` ching
2012-10-30 22:16 ` cwillu
2012-10-30 23:41 ` ching
2012-10-30 21:39 ` ching
2012-10-30 12:11 ` Felix Pepinghege
2012-10-30 12:13 ` Mitch Harder
2012-10-30 16:38 ` David Sterba
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