A point to keep in mind - if you can feel the drive moving it may be
generating errors! Depending on the drive, the errors may just be
handled internally and I can see it slowing things down though probably
would be barely noticeable. I have seen it myself with random errors
from a WD green drive disappearing when properly immobilised. When
investigating I ran across articles discussing the problem, one of which
fastened the drives to a granite slab for tests! Also see discussions
on NAS seups and vibrations affecting co located drives.
BillK
** Interesting read
https://www.ept.ca/features/everything-need-know-hard-drive-vibration/
On 27/12/21 22:15, Dale wrote:
Wols Lists wrote:
On 27/12/2021 13:40, Michael wrote:
On Monday, 27 December 2021 11:32:39 GMT Wols Lists wrote:
On 27/12/2021 11:07, Jacques Montier wrote:
Well, i don't know if my partitions are aligned or mis-aligned... How
could i get it ?
fdisk would have spewed a bunch of warnings. So you're okay.
I'm not sure of the details, but it's the classic "off by one"
problem -
if there's a mismatch between the kernel block size and the disk block
size any writes required doing a read-update-write cycle which of
course
knackered performance. I had that hit a while back.
But seeing as fdisk isn't moaning, that isn't the problem ...
Cheers,
Wol
I also thought of misaligned boundaries when I first saw the error,
but the
mention of Seagate by the OP pointed me to another edge case which
crept up
with zstd compression on ZFS. I'm mentioning it here in case it is
relevant:
https://livelace.ru/posts/2021/Jul/19/unaligned-write-command/
that might be of interest to me ... I'm getting system lockups but
it's not an SSD. I've got two IronWolves and a Barracuda.
But I notice the OP has a Barra*C*uda. Note the different spelling.
That's a shingled drive I believe, which shouldn't make a lot of
difference in light usage, but you don't want to hammer it!
Cheers,
Wol
I don't recall seeing this mentioned but this may be part of the issue
unless I'm missing something that rules this out. Could it be a drive
is a SMR drive? I recently made a new backup after wiping out the
drive. I know the backup drive is a SMR drive. At first, it copied at
a fairly normal speed but after a short time frame, it started slowing
down. At times, it would do only about 50 to 60MBs/sec. It started out
at well over 100MBs/sec which is fairly normal for this rig. I would
stop the copy process, let it catch up and restart just to give it some
time to process. I can't say it was any faster that way tho.
The way I noticed my drive was SMR, I could feel the heads going back
and forth by putting my hand on the enclosure. It had a bumpy feel to
it. You can't really hear it tho. If you can feel those little bumps
even when the drive isn't mounted, I'd be thinking it is a SMR drive.
There are also sites that you can look this sort of thing up on too. If
needed, I can go dig out some links.
Just thought it worth a mention.
Dale
:-) :-)
