From: Fiona Ebner <f.ebner@proxmox.com>
To: "DERUMIER, Alexandre" <alexandre.derumier@groupe-cyllene.com>,
"pve-devel@lists.proxmox.com" <pve-devel@lists.proxmox.com>
Subject: Re: [pve-devel] [PATCH V3 pve-storage] lvm: use blkdiscard instead cstream to saferemove drive
Date: Mon, 20 Oct 2025 16:33:22 +0200 [thread overview]
Message-ID: <efdea60f-1dbe-4912-acea-6a111087f367@proxmox.com> (raw)
In-Reply-To: <dd465feaf024d147accab248c89b101cef8df169.camel@groupe-cyllene.com>
Am 20.10.25 um 9:56 AM schrieb DERUMIER, Alexandre:
> Hi Fiona, I'm going to fix all your comment for this patch
>
>
>> + my $write_zeroes_max_bytes =
>> +
>> file_read_firstline("$sysdir/queue/write_zeroes_max_bytes") // 0;
>
>>> According to the docs: "The value 0 means that REQ_OP_WRITE_ZEROES
>>> is not supported.", so it makes sense as a fallback too. But do we
>>> need
>>> to handle that somehow below, i.e. can --zeroout still be used if the
>>> reported value is 0? Or do we need to fall back to the old way of
>>> doing it?
>
> I don't have read the code of blkdiscard yet (and don't have found
> device without write zeroes support to test), but according to redhat
> doc
> https://www.ovirt.org/develop/release-management/features/storage/wipe-volumes-using-blkdiscard.html
>
> "There are no restrictions when using blkdiscard -z, although
> blkdiscard performs roughly the same as dd if the storage does not
> support write same."
>
At a glance, the implementation of blkdiscard doesn't seem to have a
fallback and will just exit with error if the BLKZEROOUT ioctl() fails:
https://github.com/util-linux/util-linux/blob/stable/v2.41/sys-utils/blkdiscard.c#L303
_______________________________________________
pve-devel mailing list
pve-devel@lists.proxmox.com
https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
next prev parent reply other threads:[~2025-10-20 14:33 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-08-18 12:08 Alexandre Derumier via pve-devel
2025-09-22 14:06 ` Fiona Ebner
2025-10-20 7:56 ` DERUMIER, Alexandre via pve-devel
[not found] ` <dd465feaf024d147accab248c89b101cef8df169.camel@groupe-cyllene.com>
2025-10-20 14:33 ` Fiona Ebner [this message]
2025-10-20 14:37 ` DERUMIER, Alexandre via pve-devel
2025-10-20 14:54 ` Fiona Ebner
[not found] ` <7835c5768097161a8bdb53890c15ad3e4d93c7ca.camel@groupe-cyllene.com>
2025-10-20 15:15 ` Fiona Ebner
2025-10-20 15:18 ` DERUMIER, Alexandre via pve-devel
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=efdea60f-1dbe-4912-acea-6a111087f367@proxmox.com \
--to=f.ebner@proxmox.com \
--cc=alexandre.derumier@groupe-cyllene.com \
--cc=pve-devel@lists.proxmox.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