Multi global thread access to one variable (val) at the same time : Write (newVal). Then read : Check if val == newVal.
Each thread initially sleeps for a random time to create the multiple access randomly. Hopefully, crash comes.
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But still. Everything works well. However, working for an app of millions users like Zalo, it is not allowed to use such code. I worked around to find another way to simulate the crash.
What if we do some huge tasks between write and read of val ?
And Crash !
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Next step is to choose a suitable solution. Considering mutex_lock and os_unfair_lock, I pick the latter one for its speed.
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And No more Assert. The code is protected.
Further research : what is the deep difference behind mutex_lock and os_lock. What mutex_lock sacrificed for it’s speed?
