linux-ext4 - RE: planning general storage capacity for y fs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Mon, 27 Apr 2015 10:55:51 +0300
From:	"Dolev Raviv" <draviv@...eaurora.org>
To:	"'Richard Weinberger'" <richard.weinberger@...il.com>
Cc:	<linux-mtd@...ts.infradead.org>, <linux-ext4@...r.kernel.org>,
	"'Tanya Brokhman'" <tlinder@...eaurora.org>
Subject: RE: planning general storage capacity for y fs

>On Sun, Apr 26, 2015 at 1:14 PM, Dolev Raviv <draviv@...eaurora.org> wrote:
>> Hi,
>> I'm looking for guidelines for planning storage capacity. I understand 
>> it strongly depended on the usage type.
>> I want to know at what point storage fullness is effecting performance 
>> in a standard read/write partition. Do different File Systems 
>> (UBIFS/EXT4) have different full-free ratio?
>> What about read only fs? Can I plan less free space in such cases?
>>
>> I'll appreciate any input on this, for UBIFS specific and fs in general.
>
>Not sure if I got your question.
>You want to know how filesystems in general behave when they run out of free space?
>The general answer is that they need more effort to find free space.
>
>In case of UBIFS you also have to think of the garbage collector.
>See http://www.linux-mtd.infradead.org/doc/ubifs.html
>At the end of the day you'll have to run benchmarks on your own to find out how a specific filesystem behaves on your workload...
>

Thanks Richard!
Let me rephrase the question: In the past I knew there was a rule of thumb, 'leave free 30% of the storage space'. Nowadays I couldn't find any reference to this.
I was wondering, is there a known point in UBIFS (or ext4), where leaving less free storage space, that performance is dropping? Maybe a ratio of free-occupied is not the right way to look at it, but to leave a certain size free (e.g. 50MB)?

Thanks,
Dolev
-- 
Qualcomm Israel, on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project

--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html