# rand_harvestq high cpu usage when /dev/urandom is used



## alx82 (Aug 15, 2018)

Hello, 

I was just sorting randomly some jpg image files using 


```
ls *.jpg  | sort -R --random-source=/dev/urandom
```

The above command never exited, I had to kill it. Later I noticed that one of my CPU is always running 100%. top -S reveals that it is rand_harvestq kernel service. 

I read here someone saying that sysctls to turn off harvesting is documented in  random(6). I had a look at that document, but wasn't clear to me how to turn it off, I tried to play with the mask, but nothing.

This occurs on 12-ALPHA1 and 11.2.

Any idea?


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