I'm playing around with using DSLR cameras as webcams with gphoto (CLI to cameras over USB) and v4l2loopback (dummy video devices), which works with OBS but neither Skype nor VLC which will either show a black image or fail with an error message. Running VLC in verbose mode and digging a bit around showed that … Continue reading Skype and VLC cannot use v4l2loopback video device
Category: linux
Higher frame rate with Microsoft LifeCam and Linux
The Microsoft LifeCam is a versatile USB Webcam family which is supported well in Ubuntu Linux. Unfortunately it records HD videos only at low fps, but there is a workaround to get high resolution with 30 fps. Install guvcviewOpen guvcview, switch to the Video Controls tab and pick the LifeCamSelect 30/1 fps in the Frame … Continue reading Higher frame rate with Microsoft LifeCam and Linux
Nautilus browsing large windows share is slow
When browsing large windows (samba) shares with Ubuntu Nautilus (that's the equivalent of the Windows File Explorer) I observed that shares which include many files and directories (a few hundred) take a few seconds to browse over WiFi, but almost instantly display over a fast LAN. A similar difference in speed is noticeable when searching … Continue reading Nautilus browsing large windows share is slow
Constant disk access with ext4 caused by kmmp
I don't know how I never noticed this, but the mechanical hard disks in the perfect NAS emit a clicking noise at regular intervals that never stops. The NAS runs Ubuntu 18.04 server, an md software RAID 6 with dmcrypt on top, formatted with ext4. Disk I/O is way too low to show anything useful … Continue reading Constant disk access with ext4 caused by kmmp
Building the perfect, cheap DIY NAS
This post was extensively discussed on Hacker News.Alex Buznik, nas.net.ua kindly provided a two-part Russian translation: part1 and part2. This post discusses hardware considerations, installing Linux, setting up software RAID, robustness and dealing with data corruption. I've been running for a decade a self-built NAS at home, so I thought I'd write down my experience … Continue reading Building the perfect, cheap DIY NAS
First write operation to large ext4 file system is slow
I'm running a large (>20TB) ext4 file system and noticed that the first substantial write operation after mounting is very slow and involves plenty of drive activity. The reason seems to be some memory structure initialisation as described here: https://linux-ext4.vger.kernel.narkive.com/SUFNE520/ext4-slow-performance-on-first-write-after-mount The workaround is thankfully as simple as running this command in a script after mounting … Continue reading First write operation to large ext4 file system is slow
Ubuntu on the Acer Nitro 5
[updated January 2021] The Acer Nitro 5 is an interesting breed; decent computing power, a mid-range SSD, a large screen with high contrast, a decent and solid keyboard with good haptics at an ok price - but will it run Ubuntu? The Nitro comes with Windows 10 home pre-installed and UEFI secure boot enabled - … Continue reading Ubuntu on the Acer Nitro 5
Resetting a PCI device
The Wi-Fi adapter on my VivoBook 17 has been acting up under Ubuntu 18.04 LTS insofar that at a random point in time, possibly accelerated by power saving features, the Wi-Fi will stop working with suspicious syslog entries: ath10k_pci 0000:03:00.0: failed to wake target for read32 at 0x0003a028: -110 The usual tricks (suspend/resume, reload driver, … Continue reading Resetting a PCI device
Fixing random sound drops with Ubuntu; only sound device is “Dummy Output”
The title says it all; at some point Ubuntu 18.04 stops playing sound and the only available sound device is "Dummy Output". Apart from rebooting (which fixes the issue) this command executed from the terminal fixes the issue: pulseaudio -k && sudo alsa force-reload Contributed by user Kim, source: https://superuser.com/questions/17312/restart-ubuntu-sound-processes-via-command-line
A crazy server recovery
If you're a seasoned server administrator then this post will boring beyond oblivion to you; the ingredients: a headless server (no screen, keyboard)years of personal backups on a linux software RAIDa botched system upgradehappy ending The pretext Several years ago I bought an HP Proliant microserver on discount and set up a NAS with Ubuntu … Continue reading A crazy server recovery