hi, all when I used memory cgroup in latest mainline, the following error occurred: # mount -t cgroup -o memory xxx /cgroup/ # ll /cgroup/memory.memsw.* -rw-r--r--. 1 root root 0 Jun 26 23:17 /cgroup/memory.memsw.failcnt -rw-r--r--. 1 root root 0 Jun 26 23:17 /cgroup/memory.memsw.limit_in_bytes -rw-r--r--. 1 root root 0 Jun 26 23:17 /cgroup/memory.memsw.max_usage_in_bytes -r--r--r--. 1 root root 0 Jun 26 23:17 /cgroup/memory.memsw.usage_in_bytes # cat /cgroup/memory.memsw.* cat: /cgroup/memory.memsw.failcnt: Operation not supported cat: /cgroup/memory.memsw.limit_in_bytes: Operation not supported cat: /cgroup/memory.memsw.max_usage_in_bytes: Operation not supported cat: /cgroup/memory.memsw.usage_in_bytes: Operation not supported I'm confusing why it can't read memory.memsw.* files. as commit:a42c390cfa0c said, CGROUP_MEM_RES_CTLR_SWAP_ENABLED and swapaccount kernel parameter control memcg swap accounting, but I confirmed the two options all don't be set: # cat /usr/lib/modules/3.5.0-rc4+/source/.config | grep CGROUP_MEM CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y # CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED is not set CONFIG_CGROUP_MEM_RES_CTLR_KMEM=y # cat /proc/cmdline BOOT_IMAGE=/vmlinuz-3.5.0-rc4+ root=/dev/mapper/vg_amd--pike--06-lv_root ro rd.lvm.lv=vg_amd-pike-06/lv_swap rd.md=0 LANG=en_US.UTF-8 console=ttyS0,115200n81 KEYTABLE=us SYSFONT=True rd.luks=0 rd.dm=0 rd.lvm.lv=vg_amd-pike-06/lv_root so I have two problems here: 1. when kernel neither set 'CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED' nor 'swapaccount' options, why memcg have memory.memsw.* files ? 2. why we can't read memory.memsw.* ? Addition info: when I open CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED option, the above issues are gone. also I tested v3.4.0, there aren't the two issues, so please take a look. -- Thanks, Zhouping -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>