Only record zio->io_delay on reads and writes #6440
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While investigating openzfs#6425 I noticed that ioctl ZIOs were not setting zio->io_delay correctly. They would set the start time in zio_vdev_io_start(), but never set the end time in zio_vdev_io_done(), since ioctls skip it and go straight to zio_done(). This was causing spurious "delayed IO" events to appear, which would eventually get rate-limited and displayed as "Missed events" messages in zed. To get around the problem, this patch only sets zio->io_delay for read and write ZIOs, since that's all we care about anyway. Signed-off-by: Tony Hutter <hutter2@llnl.gov>
behlendorf
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gmelikov
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Aug 2, 2017
dinatale2
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Aug 2, 2017
tonyhutter
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Aug 2, 2017
While investigating openzfs#6425 I noticed that ioctl ZIOs were not setting zio->io_delay correctly. They would set the start time in zio_vdev_io_start(), but never set the end time in zio_vdev_io_done(), since ioctls skip it and go straight to zio_done(). This was causing spurious "delayed IO" events to appear, which would eventually get rate-limited and displayed as "Missed events" messages in zed. To get around the problem, this patch only sets zio->io_delay for read and write ZIOs, since that's all we care about anyway. Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Reviewed-by: George Melikov <mail@gmelikov.ru> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tony Hutter <hutter2@llnl.gov> Closes openzfs#6425 Closes openzfs#6440
tonyhutter
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While investigating #6425 I noticed that ioctl ZIOs were not setting zio->io_delay correctly. They would set the start time in zio_vdev_io_start(), but never set the end time in zio_vdev_io_done(), since ioctls skip it and go straight to zio_done(). This was causing spurious "delayed IO" events to appear, which would eventually get rate-limited and displayed as "Missed events" messages in zed. To get around the problem, this patch only sets zio->io_delay for read and write ZIOs, since that's all we care about anyway. Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Reviewed-by: George Melikov <mail@gmelikov.ru> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tony Hutter <hutter2@llnl.gov> Closes #6425 Closes #6440
Fabian-Gruenbichler
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Sep 6, 2017
While investigating openzfs#6425 I noticed that ioctl ZIOs were not setting zio->io_delay correctly. They would set the start time in zio_vdev_io_start(), but never set the end time in zio_vdev_io_done(), since ioctls skip it and go straight to zio_done(). This was causing spurious "delayed IO" events to appear, which would eventually get rate-limited and displayed as "Missed events" messages in zed. To get around the problem, this patch only sets zio->io_delay for read and write ZIOs, since that's all we care about anyway. Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov> Reviewed-by: George Melikov <mail@gmelikov.ru> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tony Hutter <hutter2@llnl.gov> Closes openzfs#6425 Closes openzfs#6440
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Description
While investigating #6425 I noticed that ioctl ZIOs were not setting
zio->io_delaycorrectly. They would set the start time inzio_vdev_io_start(), but never set the end time inzio_vdev_io_done(), since ioctls skip it and go straight tozio_done(). This was causing spurious "delayed IO" events to appear, which would eventually get rate-limited and displayed as "Missed events" messages in zed.To get around the problem, this patch only sets
zio->io_delayfor read and write ZIOs, since that's all we care about anyway.Motivation and Context
Fixes #6425
How Has This Been Tested?
Tested by doing a bunch of
zfs setcalls in a tight loop. Saw the the "Missed events" messages go away with the patch.Types of changes
Checklist:
Signed-off-by.