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Greetings all. <br>
<br>
I'm trying to run some tests with less memory than what's installed.
the 'mem=128G' option works, but it ends up putting all of the
memory on the first numa node:<br>
<blockquote>available: 2 nodes (0,8)<br>
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40<br>
41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62
63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79<br>
node 0 size: 130695 MB<br>
node 0 free: 10765 MB<br>
node 8 cpus: 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97
98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 <br>
113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128
129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 1<br>
44 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159<br>
node 8 size: 0 MB<br>
node 8 free: 0 MB<br>
</blockquote>
<br>
I want 64G on each of the 2 numa nodes. Found this kernel option:<br>
<br>
memmap=nn[KMG]$ss[KMG]<br>
[KNL,ACPI] Mark specific memory as reserved.<br>
Region of memory to be reserved is from ss
to ss+nn.<br>
Example: Exclude memory from
0x18690000-0x1869ffff<br>
memmap=64K$0x18690000<br>
or<br>
memmap=0x10000$0x18690000<br>
<br>
and it works on x86:<br>
<blockquote>available: 2 nodes (0-1)<br>
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 24 25 26 27 28 29 30 31 32
33 34 35<br>
node 0 size: 64315 MB<br>
node 0 free: 364 MB<br>
node 1 cpus: 12 13 14 15 16 17 18 19 20 21 22 23 36 37 38 39 40 41
42 43 44 45 46 47<br>
node 1 size: 64507 MB<br>
node 1 free: 134 MB<br>
</blockquote>
<br>
but i can't get it to work on Ubuntu 16.04 Power8.<br>
<blockquote>/etc/default/grub:GRUB_CMDLINE_LINUX="'memmap=64G\$384G
memmap=64G\$128G'"<br>
/boot/grub/grub.cfg: linux /vmlinux-4.10.0-33-generic
root=/dev/mapper/p215n19--vg-root ro 'memmap=64G$384G
memmap=64G$128G' splash quiet<br>
<br>
# cat /proc/cmdline <br>
root=/dev/mapper/p215n19--vg-root ro memmap=64G$384G
memmap=64G$128G splash quiet<br>
</blockquote>
<br>
someone said that it worked on RHEL, so maybe it's an
Ubuntu-specific bug.. <br>
<br>
thoughts? ideas?<br>
<br>
thanks! .bri.<br>
<br>
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