Running Pants project's tests fail on arm64 Linux machine

[alexey-tereshenkov-oxb]

Describe the bug

When running ./pants test src/python/pants/backend/project_info/count_loc_test.py in the checkout (c0386fe) of Pants repository, Pants fails with an error message:

E       ValueError: Could not initialize store for cache: "Error making env for store at \"/home/username/.cache/pants/lmdb_store/cache/3\": Cannot allocate memory"

This has likely to do something with the ARM architecture / memory management specifics.

Running ./pants version also results in an error:

$ ./pants version
22:14:41.60 [INFO] Starting: Resolving plugins: hdrhistogram, toolchain.pants.plugin==0.19.0
22:14:49.15 [INFO] Completed: Resolving plugins: hdrhistogram, toolchain.pants.plugin==0.19.0
22:14:51.80 [INFO] Initializing scheduler...
22:14:51.97 [ERROR] Could not initialize store for cache: "Error making env for store at \"/home/username/.cache/pants/lmdb_store/cache/2\": Cannot allocate memory"
...
  File "/home/username/pants/src/python/pants/engine/internals/scheduler.py", line 214, in __init__
    self._py_scheduler = native_engine.scheduler_create(
ValueError: Could not initialize store for cache: "Error making env for store at \"/home/username/.cache/pants/lmdb_store/cache/2\": Cannot allocate memory"

Use -ldebug for more logs. 
See https://www.pantsbuild.org/v2.13/docs/troubleshooting for common issues.
Consider reaching out for help: https://www.pantsbuild.org/v2.13/docs/getting-help

Running the version command with an option set is fine, see https://www.pantsbuild.org/docs/reference-global#section-local-store-files-max-size-bytes:

$ ./pants --local-store-files-max-size-bytes=25000000000 version
2.13.0.dev2

However, running the tests setting various values for the option doesn't seem to have any effect -- the tests still fail.

Pants version

2.13.0.dev2

OS

$ uname -a
Linux machine-name 4.9.140-tegra #1 SMP PREEMPT Mon Aug 12 21:29:52 PDT 2019 aarch64 aarch64 aarch64 GNU/Linux

Additional info

$ lscpu
Architecture:        aarch64
Byte Order:          Little Endian
CPU(s):              8
On-line CPU(s) list: 0-7
Thread(s) per core:  1
Core(s) per socket:  2
Socket(s):           4
Vendor ID:           Nvidia
Model:               0
Model name:          ARMv8 Processor rev 0 (v8l)
Stepping:            0x0
CPU max MHz:         2265.6001
CPU min MHz:         115.2000
BogoMIPS:            62.50
L1d cache:           64K
L1i cache:           128K
L2 cache:            2048K
L3 cache:            4096K
Flags:               fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp

$ sudo lshw -short -C memory
H/W path  Device   Class      Description
=========================================
/0/0/0             memory     64KiB L1 Cache
/0/1/0             memory     64KiB L1 Cache
/0/2/0             memory     64KiB L1 Cache
/0/3/0             memory     64KiB L1 Cache
/0/4/0             memory     64KiB L1 Cache
/0/5/0             memory     64KiB L1 Cache
/0/6/0             memory     64KiB L1 Cache
/0/7/0             memory     64KiB L1 Cache
/0/d               memory     15GiB System memory

$ inxi -m
Memory:    Using dmidecode: no smbios data. Old system?

$ dmidecode
# dmidecode 3.1
# No SMBIOS nor DMI entry point found, sorry.

[benjyw]

#17645 makes all tests pass on aarch64 linux.