Hibernation: Add check for disk space requirement

[adityagesh]

1. Hibernation requires free disk space proportional to RAM of the machine. LISA currently does not support os disk size as a requirement.
2. Azure does not support Hibernation for VM with memory larger than 256 GB

[kanchansenlaskar]

LGTM

[LiliDeng]

does get_total_memory meet your requirement?

[adityagesh]

Thanks, updated

[Copilot]

Pull request overview

This PR adds disk space validation for VM hibernation to prevent setup failures. The changes implement pre-flight checks for disk space requirements and improve error handling for space-related hibernation failures.

• Adds a new function check_hibernation_disk_requirements() that validates available disk space based on VM RAM size
• Adds error pattern detection for defragmentation space errors in the hibernation setup tool
• Integrates the disk space check into the Power test suite's before_case hook to fail fast before attempting hibernation

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.

File	Description
lisa/tools/hibernation_setup.py	Adds regex pattern and error handling for defragmentation space errors during hibernation setup
lisa/microsoft/testsuites/power/common.py	Implements new disk space validation function that checks RAM size and available disk space against hibernation requirements
lisa/microsoft/testsuites/power/power.py	Integrates disk space check into test suite setup by calling it in the before_case hook

[Copilot]

The code accesses the private method _get_field_bytes_kib directly. Consider using the existing public method get_total_memory_gb() instead, which internally calls _get_field_bytes_kib("Mem", "total") >> 20. This would be more maintainable and follow the principle of using public APIs. If more precision is needed than the integer value returned by get_total_memory_gb(), consider adding a new public method to the Free class.

Suggested change

	# Get total memory in KB
	total_memory_kb = free_tool._get_field_bytes_kib("Mem", "total")
	total_memory_gb = total_memory_kb / (1024 * 1024) # Convert KB to GB
	# Get total memory in GB using public API
	total_memory_gb = float(free_tool.get_total_memory_gb())

[Copilot]

The comment states 'Calculate required swap space' but the code actually calculates required disk space for hibernation, not swap space. The comment should be updated to accurately reflect what's being calculated: 'Calculate required disk space based on RAM size'.

Suggested change

	# Calculate required swap space based on RAM size
	# Calculate required disk space for hibernation based on RAM size

[Copilot]

The conversion from KB to GB should use 1024 ** 2 or explicitly comment that this converts KiB to GiB (using binary units). The current comment 'Convert KB to GB' is technically imprecise since the values are in kibibytes (KiB) not kilobytes (KB), as indicated by the method name _get_field_bytes_kib.

Suggested change

	total_memory_gb = total_memory_kb / (1024 * 1024) # Convert KB to GB
	total_memory_gb = total_memory_kb / (1024 * 1024) # Convert KiB to GiB (binary units)

[Copilot]

Using assert statements for error handling is not recommended in production code, as assertions can be disabled with Python's -O flag. Consider using an explicit if-check followed by raising a LisaException instead: if root_partition is None: raise LisaException(\"Unable to determine root partition disk space\").

Suggested change

	assert root_partition is not None, "Unable to determine root partition disk space"
	if root_partition is None:
	raise LisaException("Unable to determine root partition disk space")