From: Artem Bityutskiy <dedekind1@gmail.com>
To: "Gupta, Pekon" <pekon@ti.com>
Cc: "HOUR Fréderic" <frederic.hour@safran-engineering.com>,
"Kent Li" <Kent.Li@radisys.com>,
"linux-mtd@lists.infradead.org" <linux-mtd@lists.infradead.org>
Subject: Re: Corrupt empty space
Date: Fri, 21 Mar 2014 09:31:57 +0200 [thread overview]
Message-ID: <1395387117.5163.79.camel@sauron.fi.intel.com> (raw)
In-Reply-To: <20980858CB6D3A4BAE95CA194937D5E73EAB4DAF@DBDE04.ent.ti.com>
On Fri, 2014-03-21 at 07:18 +0000, Gupta, Pekon wrote:
> It's still getting discussed in [a] and [b]. But there are multiple issues to it.
>
> (1) Many hardware controllers cannot parse ECC errors in blank-pages.
> So, checking number of 0-bits in a page is done in software by comparing
> each byte with 0xff.
OK.
> (2) Counting number of 0-bits in a page in software, brings down your read-performance.
UBIFS _only_ needs this when doing recovery, which is _only_ done after
unclean reboots, and this kind of reads would be done _only_ for a
couple of max I/O units and _only_ if there is a corrupted node in the
journal.
IOW, this would be done rarely, and for just few pages on mount.
--
Best Regards,
Artem Bityutskiy
next prev parent reply other threads:[~2014-03-21 7:32 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-10 17:35 Corrupt empty space HOUR Fréderic
2014-03-11 5:31 ` Kent Li
2014-03-11 7:00 ` Gupta, Pekon
2014-03-11 7:46 ` Artem Bityutskiy
2014-03-11 8:21 ` Brian Norris
2014-03-21 7:18 ` Gupta, Pekon
2014-03-21 7:31 ` Artem Bityutskiy [this message]
2014-03-21 7:43 ` Ricard Wanderlof
2014-03-21 7:53 ` Artem Bityutskiy
2014-03-21 7:50 ` Gupta, Pekon
2014-03-21 8:13 ` Artem Bityutskiy
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