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Bugz: hysteresis
Jul. 11th, 2018 04:44 pmAaaah! Another mistery, I am wasting a second work day on. As always, after I find the root cause, this should be the most stupid and embarrassing error I made.
Here it is: I am testing a linux kernel scheduler patch I developed that improves performance of customer's benchmark. It works, but sometimes it breaks another benchmark, hence there is a bug. OK, trying to reproduce the bug.
I boot original kernel - no bug. I boot modified kernel - it takes a while to reproduce a bug. I reboot, booting a modified kernel again - the bug is instantly reproducible. But there is no state maintained between reboots in the linux kernel!!!
Here it is: I am testing a linux kernel scheduler patch I developed that improves performance of customer's benchmark. It works, but sometimes it breaks another benchmark, hence there is a bug. OK, trying to reproduce the bug.
I boot original kernel - no bug. I boot modified kernel - it takes a while to reproduce a bug. I reboot, booting a modified kernel again - the bug is instantly reproducible. But there is no state maintained between reboots in the linux kernel!!!
