Uploaded in Bionic.
** Description changed: [Impact] With v4.19, Linux gained extra fields in /proc/diskstats: https://github.com/torvalds/linux/commit/bdca3c87fb7ad1cc61d231d37eb0d8f90d001e0c [Test Case] * Follow the procedure here: https://collectd.org/wiki/index.php/First_steps and make sure disk plugin is working with let's say v4.15, then move to - >5.0 and graph will stop working, because current collectd is expecting - a precise total of fields (14), but it is now 18: + v5.0 or v5.3 and graph will stop working, because current collectd is + expecting a precise total of fields (14), but it is now 18: 15 - discards completed successfully 16 - discards merged 17 - sectors discarded 18 - time spent discarding + ===== $ uname -r 4.18.0-25-generic $ awk '{ print NF }' /proc/diskstats 14 ----- $ uname -r 5.0.0-41-generic $ awk '{ print NF }' /proc/diskstats 18 + ===== [Regression Potential] The fix has been tested in Bionic with both a kernel lt (14 fields) and gt (18 fields) than v4.19 and confirmed to work in both scenarios. If a regression have to happen it will only affect and be limited to the disk plugin. It won't affect any core functionnality nor other plugins. - The fix is found upstream for quite sometime and in Ubuntu such as Eoan/Focal(devel release). - + The fix is found upstream for quite sometime and in Ubuntu such as + Eoan/Focal(devel release). [Other Informations] Upstream bug & fix: https://github.com/collectd/collectd/issues/2951 https://github.com/collectd/collectd/commit/6ce52f70cc1e6450df3454f19743a29295b84050 $ git describe --contains 6ce52f70cc1e6450df3454f19743a29295b84050 collectd-5.8.1~3 => collectd | 5.7.2-2ubuntu1.1 | bionic-updates/universe collectd | 5.8.1-1.3ubuntu1 | eoan/universe collectd | 5.9.2.g-1ubuntu4 | focal/universe ** Description changed: [Impact] With v4.19, Linux gained extra fields in /proc/diskstats: https://github.com/torvalds/linux/commit/bdca3c87fb7ad1cc61d231d37eb0d8f90d001e0c + + The collectd disk plugin is expecting 14 fields in /proc/diskstats, but + it is not turn to 18. + + This effect the disk plugin to work at all. No more collected disk + monitoring is possible after v4.19 with current bionic collectd code. [Test Case] * Follow the procedure here: https://collectd.org/wiki/index.php/First_steps and make sure disk plugin is working with let's say v4.15, then move to v5.0 or v5.3 and graph will stop working, because current collectd is expecting a precise total of fields (14), but it is now 18: 15 - discards completed successfully 16 - discards merged 17 - sectors discarded 18 - time spent discarding ===== $ uname -r 4.18.0-25-generic $ awk '{ print NF }' /proc/diskstats 14 ----- $ uname -r 5.0.0-41-generic $ awk '{ print NF }' /proc/diskstats 18 ===== [Regression Potential] The fix has been tested in Bionic with both a kernel lt (14 fields) and gt (18 fields) than v4.19 and confirmed to work in both scenarios. If a regression have to happen it will only affect and be limited to the disk plugin. It won't affect any core functionnality nor other plugins. The fix is found upstream for quite sometime and in Ubuntu such as Eoan/Focal(devel release). [Other Informations] Upstream bug & fix: https://github.com/collectd/collectd/issues/2951 https://github.com/collectd/collectd/commit/6ce52f70cc1e6450df3454f19743a29295b84050 $ git describe --contains 6ce52f70cc1e6450df3454f19743a29295b84050 collectd-5.8.1~3 => collectd | 5.7.2-2ubuntu1.1 | bionic-updates/universe collectd | 5.8.1-1.3ubuntu1 | eoan/universe collectd | 5.9.2.g-1ubuntu4 | focal/universe -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1865895 Title: /proc/diskstats format changes in kernel v4.19 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/collectd/+bug/1865895/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
