Increase sleep time in stress_mshv_vm_create test #3114
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CVM guest takes longer time to boot. 20 seconds is the empirical boot time for a guest with 1G memory. Also, CVM guest process killing takes slightly longer time. Hence, increase the sleep timeout accordingly.
| @@ -186,7 +186,8 @@ def _mshv_stress_vm_create( | |||
| sleep_time = 10 | |||
| if guest_vm_type == "CVM": | |||
| # CVM guest take little more time to boot | |||
| sleep_time = 100 | |||
| # 20 seconds per VM (with default 1024M) | |||
| sleep_time = 20 * vm_count | |||
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Sleep is not a right fix. It needs to find a way to detect the state with an interval/timeout pattern.
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That is done intentionally. We want to launch multiple Cloud-hypervisor processes (VMs) but this is asynchronous and there is no straightforward way to determine if guest finished booting. sleep is easiest way to wait until guest boots.
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The "sleep" looks the easiest way, but it causes problems a lot. Either a longer time, or wait the long time for all cases. If others copy your solution, the problem is worse. To wait a VM started, you can use wait_tcp_port_ready method. The reboot tool use who or uptime to check last boot time to check if reboot happened.
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The VMs we launch, here from this testcase, are without any networking support, so there's no way to check network readiness. Also, sleep is only for a special vm type i.e, CVM and this has to be given as an explicit input testcase variable. By default, testcase does wait for long time.
I agree that there has to be a better way to check if VM finished its botting. If in future, cloud-hypervisor tool is used more and scenarios like these comes up more, we will plan to implement VM readiness checks.
CVM guest takes longer time to boot. 20 seconds is the empirical boot time for a guest with 1G memory. Also, CVM guest process killing takes slightly longer time. Hence, increase the sleep timeout accordingly.