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From: Wols Lists <antlists@youngman.org.uk>
To: Phil Turmel <philip@turmel.org>,
	Peter Grandi <pg@list.for.sabi.co.UK>,
	list Linux RAID <linux-raid@vger.kernel.org>
Subject: Re: SSD based sw RAID: is ERC/TLER really important?
Date: Sun, 25 Jul 2021 08:00:09 +0100	[thread overview]
Message-ID: <60FD0BF9.6060507@youngman.org.uk> (raw)
In-Reply-To: <e4ecfd01-cffc-f154-5f7c-5ca08a12fd33@turmel.org>

On 24/07/21 22:45, Phil Turmel wrote:
> I don't have data on SSD behavior without ERC.  If their retry cycle is
> exhausted within the kernel default 30 seconds, the timeout mismatch
> issue will *not* apply.

I've also seen stuff that implies (with spinning rust) that the retry
cycle can hang - a read times out, then the next attempt to read the
same data works fine.

It's *possible* the same applies to SSDs, in which case shortening the
timeout could be worthwhile.

And as Phil says, the critical fact is that the drive MUST come back
from la-la-land BEFORE the kernel times out.

Cheers,
Wol

  reply	other threads:[~2021-07-25  7:02 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-24 18:41 SSD based sw RAID: is ERC/TLER really important? Gianluca Frustagli
2021-07-24 20:19 ` Peter Grandi
2021-07-24 21:45   ` Phil Turmel
2021-07-25  7:00     ` Wols Lists [this message]
2021-07-25 10:28     ` Peter Grandi
2021-07-26  1:06       ` Phil Turmel
2021-07-26  7:57         ` Peter Grandi
2021-07-26 16:12           ` Peter Grandi
2021-07-25 11:04     ` Peter Grandi
2021-07-24 20:21 ` Andy Smith

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