From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roman Mamedov Subject: Re: Linux 5.5 Breaks Raid1 on Device instead of Partition, Unusable I/O Date: Mon, 2 Mar 2020 10:25:42 +0500 Message-ID: <20200302102542.309e2d19@natsu> References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: "David C. Rankin" Cc: mdraid List-Id: linux-raid.ids On Sun, 1 Mar 2020 19:50:03 -0600 "David C. Rankin" wrote: > Let me know if there is anything else I can send, and let me know if I > should stop the scrub or just let it run. I'm happy to run any diagnostic you > can think of that might help. Thanks. It doesn't seem convincing that the issue is raw devices vs partitions, or even kernel version related, especially since you rolled it back and the issue remains. What else you could send is "smartctl -a" of all devices; and most importantly, while the "slow" scrub is running on md4, start: iostat -x 2 /dev/sdc /dev/sdd (enlarge the terminal window) and see if any of the 2 devices is pegged into 100.0 in the last "%util" column, or just showing much higher values there than the other one. -- With respect, Roman