On Sun, 12 Aug 2018 03:51:40 +0000, Vincent Pelletier <plr.vincent@xxxxxxxxx> wrote: > This said, I was surprised by "free" output listing only a bit > above 3GB of ram total: > $ free -m > total used free shared buff/cache available > Mem: 3310 250 2867 5 192 2847 > Swap: 5015 0 5015 > Would it be an effect of KASAN ? > I also found the following line in dmesg: > [ 0.000000] Memory: 3099784K/4088348K available (14348K kernel code, 4532K rwdata, 5400K rodata, 1840K init, 9112K bss, 988564K reserved, 0K cma-reserved) > Checking pre-KASAN boots it was: > [ 0.000000] Memory: 3657884K/4088348K available (10252K kernel code, 1210K rwdata, 3216K rodata, 1548K init, 656K bss, 430464K reserved, 0K cma-reserved) Answering my own question after a bit of RTFM: KASAN uses 1 byte to track 8 bytes, so monitoring 4GB takes 512MB, so it indeed explains the vast majority of the difference in reserved memory. -- Vincent Pelletier
