sys_mem: check /proc/meminfo to get available memory #598
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sysinfo(2) is unaware of cache, but we can still fall back to it in case /proc/meminfo isn't available.
evetsso
requested review from
af-ayala,
eng-flavio-teixeira,
malcolmroberts and
regan-amd
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regan-amd
reviewed
Jun 13, 2025
| { | ||
| std::ifstream proc_meminfo("/proc/meminfo"); | ||
| std::string proc_line; | ||
| while(std::getline(proc_meminfo, proc_line)) |
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Shall we check proc_meminfo.is_open() first, maybe?
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getline will fail if the file couldn't be opened, so I don't think it'll make a difference in behaviour?
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sysinfo(2) is unaware of cache, but we can still fall back to it in case /proc/meminfo isn't available.
After testing some more on my integrated gfx1035 I realized #595 is too pessimistic. sysinfo(2) is unable to get the same information that free(1) gets, and we're really interested in the "available" number.
So for example, with 32 GiB system memory (16 GiB allocated to GPU)
freesays I have 12 GiB free and 11 GiB cached (23 GiB available). With the code that only looks atsysinfonone of the test cases will run - when we take away the 16 GiB for the GPU from 12 GIB free, there's nothing left.free(1) ultimately looks at /proc/meminfo to know its numbers so just look there first.