public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Adrian Hunter <adrian.hunter@intel.com>
To: Shuah Khan <shuahkhan@gmail.com>
Cc: David Mosberger-Tang <dmosberger@gmail.com>,
	dedekind1@gmail.com, LKML <linux-kernel@vger.kernel.org>
Subject: Re: UBIFS recovery taking too long
Date: Tue, 10 Dec 2013 09:25:12 +0200	[thread overview]
Message-ID: <52A6C1D8.7020900@intel.com> (raw)
In-Reply-To: <CAKocOOOT2J_+hmEsAnAJVWV7TOqgApd3Lih+3WaRob4e8Nex4Q@mail.gmail.com>

On 09/12/13 23:30, Shuah Khan wrote:
> Adding ubifs maintainers.
> 
> -- Shuah
> 
> On Mon, Dec 9, 2013 at 1:53 PM, David Mosberger-Tang
> <dmosberger@gmail.com> wrote:
>> I've had no luck getting any response from the linux-mtd mailing list
>> regarding the issue reported below.
>> I think it is a very serious issue since it can easily render an
>> embedded system unusable.
>>
>>   --david
>>
>> ---------- Forwarded message ----------
>> From: David Mosberger-Tang <dmosberger@gmail.com>
>> Date: Thu, Nov 7, 2013 at 11:44 AM
>> Subject: UBIFS recovery taking too long
>> To: "linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
>>
>>
>> We recently encountered a strange issue where UBIFS recovery is
>> suddenly taking a lot longer than usual (v3.7-based kernel).  In our
>> case, recovery took about 30 seconds.  This caused a serious problem
>> because our watchdog timer was set to 15 seconds, effectively
>> rendering the devices unbootable.
>>
>> Does anybody know what triggers this slow recovery mode?  Also, how
>> can we calculate a worst-case recovery time for a given flash
>> chip-size.

Slowness is probably caused by trying to make free space.  Was the file
system very full?  A smaller journal might help.

Probably the only way to determine worst-case recovery time is to test it.
Worst case conditions are likely to be a full journal and a nearly full file
system.

Ideally you want to capture a file system image that exhibits the slow
behaviour, then you can enable debug messages and see what it is doing.

>>
>> Thanks,
>>
>>   --david
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> Please read the FAQ at  http://www.tux.org/lkml/
> 
> 


  reply	other threads:[~2013-12-10  7:17 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CACwUX0PEYGsNMDvy85EsrApWzNU3iTyY-1KHMaj1ay0xxKX6RQ@mail.gmail.com>
2013-12-09 20:53 ` Fwd: UBIFS recovery taking too long David Mosberger-Tang
2013-12-09 21:30   ` Shuah Khan
2013-12-10  7:25     ` Adrian Hunter [this message]
2013-12-10 18:41       ` David Mosberger-Tang

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=52A6C1D8.7020900@intel.com \
    --to=adrian.hunter@intel.com \
    --cc=dedekind1@gmail.com \
    --cc=dmosberger@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=shuahkhan@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox