This bug is missing log files that will aid in diagnosing the problem.
While running an Ubuntu kernel (not a mainline or third-party kernel)
please enter the following command in a terminal window:
apport-collect 1900438
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable
to run this command, please add a comment stating that fact and change
the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the
Ubuntu Kernel Team.
** Changed in: linux (Ubuntu)
Status: New => Incomplete
--
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/1900438
Title:
Bcache bypasse writeback on caching device with fragmentation
Status in linux package in Ubuntu:
Incomplete
Bug description:
Hello,
An upstream bug has been opened on the matter for quite some time now [0].
I can reproduce easily on our production compute node instance, which are
trusty host with xenial hwe kernels (4.15.0-101-generic).
However due to heavy backport and such, doing real tracing is a bit hard
there.
I was able to reproduce the behavior on a hwe-bionic kernel as well.
Since most of our critical deployments use bcache, I think this is a kinda
nasty bug to have.
Reproducing the issue is relatively easy with the script provided in the bug
[1].
The script used to capture the stats is this one [2].
[0]: https://bugzilla.kernel.org/show_bug.cgi?id=206767
[1]: https://pastebin.ubuntu.com/p/YnnvvSRhXK/
[2]: https://pastebin.ubuntu.com/p/XfVpzg32sN/
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1900438/+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
