------- Comment From dougm...@us.ibm.com 2017-08-23 12:13 EDT------- By the way, I would not classify this behavior I'm seeing as a performance issue. There are hundreds of I/Os per second on each disk, and most of them are being submitted right away. But a subset of those I/Os are getting delayed for 10 minutes - if not over an hour - which is a huge disparity. The effect this can have on applications could be significant, if not critical. Some of the I/Os are taking at least 3 orders of magnitude longer than the rest. And since no timeouts are in place at this stage, I wonder if any other test frameworks even notice it. You could be hitting this in your test cases but are not aware. Consider what would happen in a database server if the rollback segment I/Os were getting delayed like this.
Some things to think about. -- 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/linux/+bug/1709889/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
