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When a lot of tasks apply to the console, it can make 'pr_info' slow. In my case, these tasks will apply to the console. I reproduced this issue using a test ko that creates many tasks, all of which just call 'pr_info'. Best regards, Ridong >> To fix this issue, call 'cond_resched' in the 'mem_cgroup_scan_tasks' >> function per 1000 iterations. For global OOM, call >> 'touch_softlockup_watchdog' per 1000 iterations to avoid this issue. > > This only hides the issue. It could be similarly fixed by simply > decreasing loglevel= ;-) > > cond_resched() in the memcg case may be OK but the arbitrary touch for > global situation may hide possibly useful troubleshooting information. > (Yeah, cond_resched() won't fit inside RCU section as in other global > task iterations.) > > 0.02€, > Michal