From 51dcf5fa00efa7947e3f454333e254ee97139226 Mon Sep 17 00:00:00 2001 From: Odin Ugedal Date: Fri, 31 May 2019 16:38:13 +0200 Subject: [PATCH] Fix cgroup hugetlb size prefix for kB The hugetlb cgroup control files (introduced here in 2012: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=abb8206cb0773) use "KB" and not "kB" (https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/mm/hugetlb_cgroup.c?h=v5.0#n349). The behavior in the kernel has not changed since the introduction, and the current code using "kB" will therefore fail on devices with small amounts of ram (see kubernetes/kubernetes#77169) running a kernel with config flag CONFIG_HUGETLBFS=y As seen from the code in "mem_fmt" inside hugetlb_cgroup.c, only "KB", "MB" and "GB" are used, so the others may be removed as well. Here is a real world example of the files (aarch64) inside the "/sys/kernel/mm/hugepages/" directory: - "hugepages-64kB" - "hugepages-2048kB" - "hugepages-32768kB" - "hugepages-1048576kB" And the corresponding cgroup files: - "hugetlb.64KB._____" - "hugetlb.2MB._____" - "hugetlb.32MB._____" - "hugetlb.1GB._____" Signed-off-by: Odin Ugedal --- utils.go | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/utils.go b/utils.go index f3129b1a..8a97d04d 100644 --- a/utils.go +++ b/utils.go @@ -168,7 +168,7 @@ func readTasksPids(path string, subsystem Name) ([]Task, error) { func hugePageSizes() ([]string, error) { var ( pageSizes []string - sizeList = []string{"B", "kB", "MB", "GB", "TB", "PB"} + sizeList = []string{"B", "KB", "MB", "GB", "TB", "PB"} ) files, err := ioutil.ReadDir("/sys/kernel/mm/hugepages") if err != nil {