I think that since I've installed an update on March 6, i started to experience freezes in the system Every few hours everything suddenly freezes and leaves no option but to restart the laptop. There's no slowness prior to the freeze. Any suggestions on debugging of this? Thank you!

Machine: Intel® Core™ i7-4810MQ CPU @ 2.80GHz × 8 15.3 GiB Intel Corporation 4th Gen Core Processor Integrated Graphics Controller (rev 06) NVIDIA Corporation GK106GLM [Quadro K2100M] (rev a1) 39.5 GB

Prior to freeze found these lines in the system logs:

nouveau 0000:01:00.0: fifo: SCHED_ERROR 0a [CTXSW_TIMEOUT]

2 Answers 2


Solution: change the driver to original Nvidia driver instead of Nouveau driver. Issue was resolved.How To Switch to NVidia driver


This is the bug of Nouveau video driver (kernel extension). For details, check the bugs at bugs.freedesktop.org or at GitLab, especially: #93629, #99900 and #100567 (which are related to SCHED_ERROR/CTXSW_TIMEOUT).

For more details, check: Ubuntu desktop hangs occasionally during regular use.

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