Some additional information and observations. What I am currently seeing with this issue on 3 systems running Ubuntu 18.04 that did not occur on the same systems that previously ran 16.04 is that the actual screen blanking in 18.04, aside from default settings or overrides, fails to turn off the monitor using DPMS as it did in 16.04, but only with nvidia binary drivers installed and only in 18.04, and only with the console blanking code in its current state.
In 18.04 without the nvidia binary driver, console blanking seems to work, as expected, with the consoleblank=n. This includes a correct power down. In 18.04 with the nvidia binary driver 340.107, console blanking only blanks the screen, but fails to power down the monitor- yet a call to vbetool dpms off does work, as do any similar calls in X for those systems that have X installed. So if vbetool dpms works with the nvidia binary driver and the console blanking code no longer does, I am half way to an assumption that the dpms code in the console blanking has changed, with some reservation that possibly the latest nvidia binary driver doesn't like the way the call is coming from the newly changed console blanking code. This problem did not exist in 16.04, on any of our systems to my knowledge, with or without a graphical desktop installed and with or without a binary driver installed. >From my perspective, this isn't an issue of default blanking behaviour, but rather an issue with a broken dpms call in 18.04 to a system with the nvidia binary driver. Other calls, such as vbetool dpms off work as do those within graphical desktop systems such as those like the one that xscreensaver uses. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/869017 Title: Ubuntu server enables screenblanking, concealing crashdumps (DPMS is not used) Status in kbd package in Ubuntu: Invalid Status in linux package in Ubuntu: Fix Released Status in kbd source package in Zesty: Invalid Status in linux source package in Zesty: Fix Released Status in kbd package in Debian: Fix Released Bug description: James Rice of Jump Networks noticed that there is a screen-blanker enabled on Ubuntu Server. James notes that this blanking is not enabling DPMS power saving (thereby negating any power-saving benefit), and is simply turning the screen content blank. This means that the crash output is invisible which is unhelpful on a server (virtual or otherwise). Ideally the screen should (at a minimum) be turned on and unblanked at the point of an OOPs/crash being printed. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kbd/+bug/869017/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
