Memory tests behave differently on one vs. several tests

[tommyod]

There seems to be some state or overhead when running multiple memray tests.

• Running all three tests in one go reports high memory usage for the first one, lower for the remaining two tests
• Running one at a time reports a relatively high memory usage for each test

Running all tests

pytest tests -k memory --memray 

==================================================================================== MEMRAY REPORT ===
Allocation results for tests/test_esmda.py::TestESMDAMemory::test_ESMDA_memory_usage_subspace_inversion_without_overwrite at the high watermark

	 📦 Total memory allocated: 127.2MiB
	 📏 Total allocations: 194
	 📊 Histogram of allocation sizes: |▁ █   ▁ ▃|


Allocation results for tests/test_sies.py::test_memory_usage at the high watermark

	 📦 Total memory allocated: 63.8MiB
	 📏 Total allocations: 237
	 📊 Histogram of allocation sizes: |▂ ▄   ▅ █|


Allocation results for tests/test_esmda.py::TestESMDAMemory::test_ESMDA_memory_usage_subspace_inversion_with_overwrite at the high watermark

	 📦 Total memory allocated: 54.8MiB
	 📏 Total allocations: 156
	 📊 Histogram of allocation sizes: |▆   ▅   █|

Running individually

pytest tests -k test_ESMDA_memory_usage_subspace_inversion_without_overwrite --memray

==================================================================================== MEMRAY REPORT ===
Allocation results for tests/test_esmda.py::TestESMDAMemory::test_ESMDA_memory_usage_subspace_inversion_without_overwrite at the high watermark

	 📦 Total memory allocated: 127.2MiB
	 📏 Total allocations: 194
	 📊 Histogram of allocation sizes: |▁ █   ▁ ▃|

---

pytest tests -k test_memory_usage --memray

==================================================================================== MEMRAY REPORT ===
Allocation results for tests/test_sies.py::test_memory_usage at the high watermark

	 📦 Total memory allocated: 127.8MiB
	 📏 Total allocations: 255
	 📊 Histogram of allocation sizes: |█ ▅ █ ▃ █|

---

pytest tests -k test_ESMDA_memory_usage_subspace_inversion_with_overwrite --memray

==================================================================================== MEMRAY REPORT ===
Allocation results for tests/test_esmda.py::TestESMDAMemory::test_ESMDA_memory_usage_subspace_inversion_with_overwrite at the high watermark

	 📦 Total memory allocated: 118.8MiB
	 📏 Total allocations: 186
	 📊 Histogram of allocation sizes: |▁ █   ▁ ▃|

[tommyod]

There also seems to be a bit of state between runs:

<change the test>


(venv) > $ pytest tests --memray -k test_esmda_inversion_memory

==================================================================================== MEMRAY 
Allocation results for tests/test_esmda_inversion.py::test_esmda_inversion_memory at the high watermark

	 📦 Total memory allocated: 128.2MiB




(venv) > $ pytest tests --memray -k test_esmda_inversion_memory
==================================================================================== MEMRAY 
Allocation results for tests/test_esmda_inversion.py::test_esmda_inversion_memory at the high watermark

	 📦 Total memory allocated: 127.2MiB