We have some machines with multiple memory types like below, which have one fast (DRAM) memory node and two slow (persistent memory) memory nodes. According to current node demotion policy, if node 0 fills up, its memory should be migrated to node 1, when node 1 fills up, its memory will be migrated to node 2: node 0 -> node 1 -> node 2 ->stop. But this is not efficient and suitbale memory migration route for our machine with multiple slow memory nodes. Since the distance between node 0 to node 1 and node 0 to node 2 is equal, and memory migration between slow memory nodes will increase persistent memory bandwidth greatly, which will hurt the whole system's performance. Thus for this case, we can treat the slow memory node 1 and node 2 as a whole slow memory region, and we should migrate memory from node 0 to node 1 and node 2 if node 0 fills up. This patch changes the node_demotion data structure to support multiple target nodes, and establishes the migration path to support multiple target nodes with validating if the node distance is the best or not. available: 3 nodes (0-2) node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 node 0 size: 62153 MB node 0 free: 55135 MB node 1 cpus: node 1 size: 127007 MB node 1 free: 126930 MB node 2 cpus: node 2 size: 126968 MB node 2 free: 126878 MB node distances: node 0 1 2 0: 10 20 20 1: 20 10 20 2: 20 20 10 Link: https://lkml.kernel.org/r/00728da107789bb4ed9e0d28b1d08fd8056af2ef.1636697263.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Zi Yan <ziy@nvidia.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Yang Shi <shy828301@gmail.com> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: zhongjiang-ali <zhongjiang-ali@linux.alibaba.com> Cc: Xunlei Pang <xlpang@linux.alibaba.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
||
---|---|---|
Documentation | ||
LICENSES | ||
arch | ||
block | ||
certs | ||
crypto | ||
drivers | ||
fs | ||
include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
mm | ||
net | ||
samples | ||
scripts | ||
security | ||
sound | ||
tools | ||
usr | ||
virt | ||
.clang-format | ||
.cocciconfig | ||
.get_maintainer.ignore | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
COPYING | ||
CREDITS | ||
Kbuild | ||
Kconfig | ||
MAINTAINERS | ||
Makefile | ||
README |
README
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.