[systemd-devel] sysrq+t "missed kernel messages"

[Chris Murphy]

When I issue sysrq+t I'm getting a lot of "missed kernel messages"
messages in the journal. Are there really hundreds of messages
missing? Is this expected? I could increase the kernel message buffer
to 1M and see if they're really missing I guess; the sysrq+t output is
too big to fit by default and dmesg doesn't contain the entire output.
It'd be nice if systemd-journald can include the entire output though.

Aug 20 12:19:50 f24m kernel: Call Trace:
Aug 20 12:19:50 f24m kernel:  [<ffffffff97801805>] schedule+0x35/0x80
Aug 20 12:19:50 f24m kernel:  [<ffffffff97109fc8>] rcu_nocb_kthread+0xe8/0x490
Aug 20 12:19:50 f24m kernel:  [<ffffffff97109ee0>] ?
get_state_synchronize_rcu+0x20/0x20
Aug 20 12:19:50 f24m kernel:  [<ffffffff970c1cc8>] kthread+0xd8/0xf0
Aug 20 12:19:50 f24m kernel:  [<ffffffff9780617f>] ret_from_fork+0x1f/0x40
Aug 20 12:19:50 f24m kernel:  [<ffffffff970c1bf0>] ?
kthread_worker_fn+0x180/0x180
Aug 20 12:19:50 f24m kernel: rcuob/2         S ffff9dd625c83e30     0
  30      2 0x00000000
Aug 20 12:19:50 f24m kernel:  ffff9dd625c83e30 00ff9dd625c83e80
ffff9dd625c79e80 ffff9dd626295b80
Aug 20 12:19:50 f24m kernel:  ffff9dd625c83e38 ffff9dd625c84000
ffff9dd62fa9a140 ffff9dd625c79e80
Aug 20 12:19:50 f24m kernel:  0000000000000002 0000000000000000
ffff9dd625c83e48 ffffffff97801805
Aug 20 12:19:50 f24m kernel: Call Trace:
Aug 20 12:19:50 f24m kernel:  [<ffffffff97801805>] schedule+0x35/0x80
Aug 20 12:19:50 f24m kernel:  [<ffffffff97109fc8>] rcu_nocb_kthread+0xe8/0x490
Aug 20 12:19:50 f24m kernel:  [<ffffffff97109ee0>] ?
get_state_synchronize_rcu+0x20/0x20
Aug 20 12:19:50 f24m kernel:  [<ffffffff970c1cc8>] kthread+0xd8/0xf0
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 40 kernel messages
Aug 20 12:19:50 f24m kernel: Call Trace:
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 338 kernel messages
Aug 20 12:19:50 f24m kernel:  [<ffffffff970c1cc8>] kthread+0xd8/0xf0
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 117 kernel messages
Aug 20 12:19:50 f24m kernel:  ffff9dd62593d4b0 ffff9dd62593d480
ffff9dd62596fe40 ffffffff97801805
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 126 kernel messages
Aug 20 12:19:50 f24m kernel:  [<ffffffff970c1cc8>] kthread+0xd8/0xf0
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 114 kernel messages
Aug 20 12:19:50 f24m kernel: Call Trace:
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 107 kernel messages
Aug 20 12:19:50 f24m kernel: Call Trace:
Aug 20 12:19:50 f24m systemd-journald[561]: Missed 109 kernel messages


-- 
Chris Murphy