Dynamic disks, switch them too
# Little story
*I have to tell a story here, if you just want the important main information: TL;DR at the bottom my dude. :\**
Two identical mini PCs that were intended for use in a control cabinet were disposed of at work. One of them had a simple defect: the hard drive was dead. These devices are disposed of even if they are repairable. (Because of reasons)
So I quickly replaced the hard drive and one of them worked again. Pretty nice, passively cooled single-board computer, relatively powerful. (As a new purchase, it would cost around €500.)
So I took it with me to build a small homemade NAS, because it still had two free SATA ports and some space in the case for two 2.5" hard drives. I quickly installed Linux on it to test it out. It worked wonderfully and without any additional driver searches.
But there was a problem: there was no standard way to power the additional SSDs. Fortunately, there was a free USB 2.0 header on the board. I read up on this and found that these things deliver around 2.5W @ 5V. The sources were contradictory on this point. And unfortunately, the mind-reading, perfect Google of 2013 no longer exists. :P So I was not sure. I decided to just give it a try. I ordered an SSD that, according to the shop filter, needed around 2.5W. And I powered it via the USB header. It, worked! (Even if datasheet said afterwards: yo need 3W on write.)
From this point on, I invested a lot of time reading up on the subject. I had to rack my brains a lot because some things didn't work right away the way I imagined they would.
I set up Openmediavaul, but it was buggy, so I switched to a server distro with SFTPGo because it looked nice and simple. And it was.
Just as I had started migrating the data, I noticed a problem that would keep me busy for a month: data transfers were painfully slow. Definitely not what I wanted.
So I did a lot of research because I didn't want to wipe the setup again. But I just couldn't find any useful information. ^((Google bad)) I benchmarked my network connection between PC \~ NAS, 980Mbps, everything fine. So I suspected the problem was with SFTPGo and eventually gave up.
Next attempt: TrueNAS. Everything set up, which took longer again due to problems with access rights and stuff, because of multiprotocol overlaps. Then I started migrating the data... Slow again, \~ 5MB/s -.-
I continued to suspect that the problem was with the software and spent ages researching solutions and configuration options. Nothing. Maybe it is a problem with the power supply after all? I connected it to my PC's power supply. Same problem. Then I benchmarked the hard drive. (Yes, I realize I should have done that beforehand. :P)
dd if=/dev/zero of=/mnt/ssd/test/test.txt bs=1G count=1 oflag=dsync
1+0 Datensätze ein
1+0 Datensätze aus
1073741824 Byte (1,1 GB, 1,0 GiB) kopiert, 3,52969 s, 304 MB/s
Everything is fine. So WTF is wrong!? Why are data transfers as slow as with a fucking old USB stick!?
Yea... How about a benchmark of the read speed on my PC? Even though I don't think that can be the reason...
time dd if=/mnt/dynamic-ntfs/Videos/Filme/Interstellar.mp4 of=/dev/null bs=8k
^C77409+0 Datensätze ein
77408+0 Datensätze aus
634126336 Byte (634 MB, 605 MiB) kopiert, 39,8158 s, 15,9 MB/s
o\_\_\_\_\_o
Yea... Thing is: I switched to Linux. And did you notice where the file is? Yea, its a mount.
I've created an dynamic disk under windows. Thats something like LVM, to access multiple physical drives as one logical one. But when I switched to Linux, I didn't want to wipe them out. So I looked for a way to mount them under Linux. The ldmtool is available for this purpose. ([ArchWiki](https://wiki.archlinux.org/noscript/Dynamic_disks))
It didn't even occur to me. I hadn't even remembered that I had mounted the SSDs that way. So I was looking in the wrong place the whole time. And I never noticed it before, but ldmtool mounted drives are just really slow.
A little story about how you can spend a long time looking for the cause of a
# Little story
*I have to tell a story here, if you just want the important main information: TL;DR at the bottom my dude. :\**
Two identical mini PCs that were intended for use in a control cabinet were disposed of at work. One of them had a simple defect: the hard drive was dead. These devices are disposed of even if they are repairable. (Because of reasons)
So I quickly replaced the hard drive and one of them worked again. Pretty nice, passively cooled single-board computer, relatively powerful. (As a new purchase, it would cost around €500.)
So I took it with me to build a small homemade NAS, because it still had two free SATA ports and some space in the case for two 2.5" hard drives. I quickly installed Linux on it to test it out. It worked wonderfully and without any additional driver searches.
But there was a problem: there was no standard way to power the additional SSDs. Fortunately, there was a free USB 2.0 header on the board. I read up on this and found that these things deliver around 2.5W @ 5V. The sources were contradictory on this point. And unfortunately, the mind-reading, perfect Google of 2013 no longer exists. :P So I was not sure. I decided to just give it a try. I ordered an SSD that, according to the shop filter, needed around 2.5W. And I powered it via the USB header. It, worked! (Even if datasheet said afterwards: yo need 3W on write.)
From this point on, I invested a lot of time reading up on the subject. I had to rack my brains a lot because some things didn't work right away the way I imagined they would.
I set up Openmediavaul, but it was buggy, so I switched to a server distro with SFTPGo because it looked nice and simple. And it was.
Just as I had started migrating the data, I noticed a problem that would keep me busy for a month: data transfers were painfully slow. Definitely not what I wanted.
So I did a lot of research because I didn't want to wipe the setup again. But I just couldn't find any useful information. ^((Google bad)) I benchmarked my network connection between PC \~ NAS, 980Mbps, everything fine. So I suspected the problem was with SFTPGo and eventually gave up.
Next attempt: TrueNAS. Everything set up, which took longer again due to problems with access rights and stuff, because of multiprotocol overlaps. Then I started migrating the data... Slow again, \~ 5MB/s -.-
I continued to suspect that the problem was with the software and spent ages researching solutions and configuration options. Nothing. Maybe it is a problem with the power supply after all? I connected it to my PC's power supply. Same problem. Then I benchmarked the hard drive. (Yes, I realize I should have done that beforehand. :P)
dd if=/dev/zero of=/mnt/ssd/test/test.txt bs=1G count=1 oflag=dsync
1+0 Datensätze ein
1+0 Datensätze aus
1073741824 Byte (1,1 GB, 1,0 GiB) kopiert, 3,52969 s, 304 MB/s
Everything is fine. So WTF is wrong!? Why are data transfers as slow as with a fucking old USB stick!?
Yea... How about a benchmark of the read speed on my PC? Even though I don't think that can be the reason...
time dd if=/mnt/dynamic-ntfs/Videos/Filme/Interstellar.mp4 of=/dev/null bs=8k
^C77409+0 Datensätze ein
77408+0 Datensätze aus
634126336 Byte (634 MB, 605 MiB) kopiert, 39,8158 s, 15,9 MB/s
o\_\_\_\_\_o
Yea... Thing is: I switched to Linux. And did you notice where the file is? Yea, its a mount.
I've created an dynamic disk under windows. Thats something like LVM, to access multiple physical drives as one logical one. But when I switched to Linux, I didn't want to wipe them out. So I looked for a way to mount them under Linux. The ldmtool is available for this purpose. ([ArchWiki](https://wiki.archlinux.org/noscript/Dynamic_disks))
It didn't even occur to me. I hadn't even remembered that I had mounted the SSDs that way. So I was looking in the wrong place the whole time. And I never noticed it before, but ldmtool mounted drives are just really slow.
A little story about how you can spend a long time looking for the cause of a
problem in the wrong place(s)...
^((Nevertheless, Google is now only a shadow of its former self. And that was time consuming as well.))
# TL;DR
If you are using ldmtool to mount windows dynamic disks, you should know: that the overall I/O performance is really low. Consider to switch them to LVM, BTRFS in JBOD config or something like that.
https://redd.it/1m97p1c
@r_linux
^((Nevertheless, Google is now only a shadow of its former self. And that was time consuming as well.))
# TL;DR
If you are using ldmtool to mount windows dynamic disks, you should know: that the overall I/O performance is really low. Consider to switch them to LVM, BTRFS in JBOD config or something like that.
https://redd.it/1m97p1c
@r_linux
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This Week in Plasma: Printer Ink Level Monitoring
https://blogs.kde.org/2025/07/26/this-week-in-plasma-printer-ink-level-monitoring/
https://redd.it/1m9ghy6
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https://blogs.kde.org/2025/07/26/this-week-in-plasma-printer-ink-level-monitoring/
https://redd.it/1m9ghy6
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KDE Blogs
This Week in Plasma: Printer Ink Level Monitoring
Welcome to a new issue of This Week in Plasma!
Every week we cover the highlights of what’s happening in the world of KDE Plasma and its associated apps like Discover, System Monitor, and more.
Every week we cover the highlights of what’s happening in the world of KDE Plasma and its associated apps like Discover, System Monitor, and more.
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Yall wanna see so many people that hate Linux for some reason but don't even know what they're talking about?
https://redd.it/1m9i46t
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https://redd.it/1m9i46t
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OpenPGP for application developers
https://openpgp.dev/book/index.html
https://redd.it/1m9jusg
@r_linux
https://openpgp.dev/book/index.html
https://redd.it/1m9jusg
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OpenPGP for application developers
The essential OpenPGP guide for application developers. Learn the OpenPGP standard for cryptographic operations and how to implement it in your projects. Gain insights into digital signatures, key management, certificates, and more. Version agnostic.
SPDIF TosLink Troubles (GNU-Linux)
If anyone has had issues with PCM 48 over TosLink—Zorin OS for some reasons cooks Fedora based distros and NixOS in the task.
I don't really know why and I've already spent way too much time trying to solve it on NixOS.
But basically, distros other than Zorin were just crackling on playback no matter what I'd do. So in the off chance you have this issue too, give Zorin OS a go before you give up 💙
And if you know the reason why, feel free to leave a comment about it! There aren't many conversations about TosLink around.
https://redd.it/1m9irc6
@r_linux
If anyone has had issues with PCM 48 over TosLink—Zorin OS for some reasons cooks Fedora based distros and NixOS in the task.
I don't really know why and I've already spent way too much time trying to solve it on NixOS.
But basically, distros other than Zorin were just crackling on playback no matter what I'd do. So in the off chance you have this issue too, give Zorin OS a go before you give up 💙
And if you know the reason why, feel free to leave a comment about it! There aren't many conversations about TosLink around.
https://redd.it/1m9irc6
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Linux Will Finally Be Able To Reboot Apple M1/M2 Macs With The v6.17 Kernel
https://www.phoronix.com/news/Linux-6.17-Apple-SMC
https://redd.it/1m9m0dk
@r_linux
https://www.phoronix.com/news/Linux-6.17-Apple-SMC
https://redd.it/1m9m0dk
@r_linux
Phoronix
Linux Will Finally Be Able To Reboot Apple M1/M2 Macs With The v6.17 Kernel
While there have been various elements of the Apple M1 and M2 SoC support in the mainline Linux kernel along with support for various Macs, different features have been missing from the upstream kernel such as the Apple GPU kernel graphics driver as one big…
The Linux Concept Journey — kexec (Kernel Execute)
“kexec” (Kernel Execute) is a set of Linux system calls (https://medium.com/@boutnaru/the-linux-concept-journey-syscalls-system-calls-efcd7703e072) which provides the ability to load and boot\\reboot into a new kernel from the currently running kernel. It can help in cases in which we want to reboot very fast without waiting for an entire boot process (https://wiki.archlinux.org/noscript/Kexec). Moreover, we can use the “/sbin/kexec” binary for that using the following syntax: “kexec -l kernel-image — append=command-line-options — initrd=initrd-image” (https://linux.die.net/man/8/kexec).
Overall, the difference between a normal “system boot” and a “kexec boot” is that the hardware initialization performed by the firmware (like BIOS\\UEFI) is not done in case of a “kexec boot” (https://linux.die.net/man/8/kexec). Thus, “kexec boot” loads a new kernel and jumps to it while bypassing the firmware and the bootloader like GRUB (https://medium.com/@boutnaru/the-linux-concept-journey-gnu-grub-gnu-grand-unified-bootloader-0a1e64067315). Examples of use-case are: first step in generating a crash dump and during kernel development when frequently building and rebooting the kernel (https://blogs.oracle.com/linux/post/reboot-faster-with-kexec).
Lastly, a new kernel image can be loaded from a memory segment using the “kexec_load” syscall (https://elixir.bootlin.com/linux/v6.15.5/source/kernel/kexec.c#L242) or from a file using the “kexec_file_load” syscall (https://elixir.bootlin.com/linux/v6.15.5/source/kernel/kexec\_file.c#L332). Also, for enabling the “kexec” system call we should enable “CONFIG_KEXEC” (https://elixir.bootlin.com/linux/v6.15.5/source/kernel/Kconfig.kexec#L20). By the way, “kdump” (Kernel Dump) is based on kexec for quickly booting to a dump-capture kernel in case a dump of the system kernel’s memory needs to be taken. An example is when the system panics (https://docs.kernel.org/admin-guide/kdump/kdump.html) — as shown in the diagram below (https://cloud.tencent.com/developer/article/2431825).
https:\/\/cloud.tencent.com\/developer\/article\/2431825
https://redd.it/1m9ocdh
@r_linux
“kexec” (Kernel Execute) is a set of Linux system calls (https://medium.com/@boutnaru/the-linux-concept-journey-syscalls-system-calls-efcd7703e072) which provides the ability to load and boot\\reboot into a new kernel from the currently running kernel. It can help in cases in which we want to reboot very fast without waiting for an entire boot process (https://wiki.archlinux.org/noscript/Kexec). Moreover, we can use the “/sbin/kexec” binary for that using the following syntax: “kexec -l kernel-image — append=command-line-options — initrd=initrd-image” (https://linux.die.net/man/8/kexec).
Overall, the difference between a normal “system boot” and a “kexec boot” is that the hardware initialization performed by the firmware (like BIOS\\UEFI) is not done in case of a “kexec boot” (https://linux.die.net/man/8/kexec). Thus, “kexec boot” loads a new kernel and jumps to it while bypassing the firmware and the bootloader like GRUB (https://medium.com/@boutnaru/the-linux-concept-journey-gnu-grub-gnu-grand-unified-bootloader-0a1e64067315). Examples of use-case are: first step in generating a crash dump and during kernel development when frequently building and rebooting the kernel (https://blogs.oracle.com/linux/post/reboot-faster-with-kexec).
Lastly, a new kernel image can be loaded from a memory segment using the “kexec_load” syscall (https://elixir.bootlin.com/linux/v6.15.5/source/kernel/kexec.c#L242) or from a file using the “kexec_file_load” syscall (https://elixir.bootlin.com/linux/v6.15.5/source/kernel/kexec\_file.c#L332). Also, for enabling the “kexec” system call we should enable “CONFIG_KEXEC” (https://elixir.bootlin.com/linux/v6.15.5/source/kernel/Kconfig.kexec#L20). By the way, “kdump” (Kernel Dump) is based on kexec for quickly booting to a dump-capture kernel in case a dump of the system kernel’s memory needs to be taken. An example is when the system panics (https://docs.kernel.org/admin-guide/kdump/kdump.html) — as shown in the diagram below (https://cloud.tencent.com/developer/article/2431825).
https:\/\/cloud.tencent.com\/developer\/article\/2431825
https://redd.it/1m9ocdh
@r_linux
Medium
The Linux Concept Journey — Syscalls (System Calls)
Syscalls (aka “System Calls”) are a fundamental interface between user-mode code and the Linux kernel. Most of the user-mode developers…
Which is the single most time saving hack you used in Linux?
Which commands, tool or hack or anything has saved a lot of time for you on repeated tasks that you do daily? What thing in your experiences saved you much time and effort that you thought you should have learned earlier?
I just used alias "c" for clear and it saves a lot of time and effort.
https://redd.it/1m9ra4r
@r_linux
Which commands, tool or hack or anything has saved a lot of time for you on repeated tasks that you do daily? What thing in your experiences saved you much time and effort that you thought you should have learned earlier?
I just used alias "c" for clear and it saves a lot of time and effort.
https://redd.it/1m9ra4r
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Suggestions for M.2 WiFi / Bluetooth card that have good compatibility with Linux?
Hey all - noscript says it all. Looking for suggestions for M.2 WiFi / Bluetooth cards that have good compatibility with Linux?
I've got 2 little HP Elitedesk 701 AMD A10-powered mini PCs with Intel 7200-something series WiFi cards that do not play nice with Linux at all, so was just looking for something that would work and is plug and play.
Thanks!
https://redd.it/1m9sjae
@r_linux
Hey all - noscript says it all. Looking for suggestions for M.2 WiFi / Bluetooth cards that have good compatibility with Linux?
I've got 2 little HP Elitedesk 701 AMD A10-powered mini PCs with Intel 7200-something series WiFi cards that do not play nice with Linux at all, so was just looking for something that would work and is plug and play.
Thanks!
https://redd.it/1m9sjae
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Linux 6.17 Will Be Exciting With Intel "Project Battlematrix" GPU Driver Changes & More
https://www.phoronix.com/news/Linux-6.17-Early-Features
https://redd.it/1m9tmnh
@r_linux
https://www.phoronix.com/news/Linux-6.17-Early-Features
https://redd.it/1m9tmnh
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Phoronix
Linux 6.17 Will Be Exciting With Intel "Project Battlematrix" GPU Driver Changes & More
With Linux 6.16 expected to be released on Sunday unless an extra week of testing is deemed necessary, the Linux 6.17 merge window will then kickoff the next day
Linux Kernel Proposal Documents Rules For Using AI Coding Assistants
https://www.phoronix.com/news/Linux-Kernel-AI-Docs-Rules
https://redd.it/1m9uub4
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https://www.phoronix.com/news/Linux-Kernel-AI-Docs-Rules
https://redd.it/1m9uub4
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Phoronix
Linux Kernel Proposal Documents Rules For Using AI Coding Assistants
Longtime Linux developer Sasha Levin of NVIDIA (and formerly of Google and Microsoft) as well as being the Linux LTS kernel co-maintainer today proposed a Linux kernel AI coding assistant configuration and documentation/rules for contributing to the Linux…
parallel-disk-usage (pdu) is a CLI tool that renders disk usage of a directory tree in an ASCII graph. Version 0.20.0 now has the ability to detect and remove hardlink sizes from totals.
https://redd.it/1m9v27o
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https://redd.it/1m9v27o
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Intel oneDNN 3.9 Making More Preparations For Xe3, Nova Lake & Diamond Rapids
https://www.phoronix.com/news/Intel-oneDNN-3.9-RC
https://redd.it/1m9tmxy
@r_linux
https://www.phoronix.com/news/Intel-oneDNN-3.9-RC
https://redd.it/1m9tmxy
@r_linux
Phoronix
Intel oneDNN 3.9 Making More Preparations For Xe3, Nova Lake & Diamond Rapids
Released on Friday was a new version of the oneDNN deep neural network library maintained by Intel and the UXL Foundation
How we Rooted Copilot (cause it's running from a customized Ubuntu container)
https://research.eye.security/how-we-rooted-copilot/
https://redd.it/1ma12we
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https://research.eye.security/how-we-rooted-copilot/
https://redd.it/1ma12we
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Eye Research
How we Rooted Copilot
After a long week, the Eye Security Research Team thought it was time for a small light-hearted distraction. So we rooted Copilot.
Oh blessed day, my dad was down with a dual boot to try and daily drive Linux Mint! His first Linux distro!
Hello everyone, my dad who got me into computers back in 2006 or so has gotten out of them and just stuck to windows, but today after he's gotten a new desktop a while back he's down with trying to daily drive linux mint!
He uses SDRs and other radios and softwares but they're usually old so I feel we should be able to use them on wine, if not that's the reason for the dual boot, he doesn't use it daily or even weekly.
He spends a lot of time trying to make windows faster, more secure, etc. but he really can't so I think he'll love playing with this, not having to play with it, or maybe even learning about real security (I'm in Purple Team security so I can help guide him and teach him) like firewalls and static code scanners and stuff instead of Geek Squad and random youtube tutorials lol
Just was excited and wanted to share!
Cheers!
https://redd.it/1ma7ogk
@r_linux
Hello everyone, my dad who got me into computers back in 2006 or so has gotten out of them and just stuck to windows, but today after he's gotten a new desktop a while back he's down with trying to daily drive linux mint!
He uses SDRs and other radios and softwares but they're usually old so I feel we should be able to use them on wine, if not that's the reason for the dual boot, he doesn't use it daily or even weekly.
He spends a lot of time trying to make windows faster, more secure, etc. but he really can't so I think he'll love playing with this, not having to play with it, or maybe even learning about real security (I'm in Purple Team security so I can help guide him and teach him) like firewalls and static code scanners and stuff instead of Geek Squad and random youtube tutorials lol
Just was excited and wanted to share!
Cheers!
https://redd.it/1ma7ogk
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