------- Comment From dougm...@us.ibm.com 2017-08-11 07:44 EDT------- Testing shows that this commit appears to fix the problem. After 20 hours, no evidence of stalled I/Os.
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5be6b75610cefd1e21b98a218211922c2feb6e08 This fixes a problem introduced by having two modes of operation for cfq that each uses a different timebase, and not having separate scheduling delay (time limit before forcing I/O submit) settings. What appears to be the default mode, "iops", ended up using a delay that allowed I/Os to be postponed for up to 200000000 jiffies (which is hundreds of hours). -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1709889 Title: Ubuntu 17.04: Bug in cfq scheduler, I/Os do not get submitted to adapter for a very long time. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1709889/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
