我正在通过 bash 脚本运行复杂的工作流程，这些脚本使用外部程序/命令来执行不同的操作。它运行了几个小时，但突然 OOM 杀手终止了我的工作流程或整个 bash 脚本的程序，即使仍然有足够的内存可用。我用 ps 命令每 0.01 秒记录一次内存使用情况，根本没有增加或变化，仍然有几个 GB 可用。但是突然从一个内存快照到下一个内存快照，某个进程被 OOM 杀手终止。这是内存使用情况的典型 ps 快照：
PID %MEM RSS VSZ COMMAND USER
139443 1.2 1651768 8622936 java jadzia
123601 0.1 163352 523068 obabel jadzia
139355 0.0 5488 253120 srun jadzia
125747 0.0 5252 365088 obabel jadzia
125757 0.0 5252 365088 obabel jadzia
125388 0.0 5224 365088 obabel jadzia
125824 0.0 3764 267736 obabel jadzia
21062 0.0 3724 128628 bash jadzia
125778 0.0 3628 267736 obabel jadzia
127018 0.0 1904 113416 bash jadzia
126127 0.0 1812 161476 ps jadzia
139526 0.0 1740 10288 one-step.sh jadzia
139508 0.0 1736 10252 one-step.sh jadzia
139473 0.0 1728 10256 one-step.sh jadzia
139477 0.0 1728 10252 one-step.sh jadzia
139558 0.0 1724 10252 one-step.sh jadzia
139585 0.0 1724 10252 one-step.sh jadzia
139539 0.0 1704 10292 one-step.sh jadzia
139370 0.0 1688 9676 one-step.sh jadzia
139485 0.0 1688 10200 one-step.sh jadzia
125742 0.0 1544 10252 one-step.sh jadzia
125752 0.0 1532 10252 one-step.sh jadzia
125772 0.0 1532 10256 one-step.sh jadzia
125819 0.0 1532 10252 one-step.sh jadzia
125363 0.0 1508 10292 one-step.sh jadzia
123586 0.0 1496 10200 one-step.sh jadzia
139357 0.0 860 48364 srun jadzia
104975 0.0 724 6448 ng jadzia
91240 0.0 720 6448 ng jadzia
所有进程的 RSS 总和始终保持在 3GB 以下且不会出现峰值。
查看 dmesg 输出时，条目显示调用 oom-killer 的是不同的程序：从外部二进制程序（例如 obabel）到“tr”实用程序或执行命令本身的 bash 脚本。以下是两个不同的 dmesg 示例，显示了 oom 事件：
[Thu Nov 1 15:15:27 2018] tr invoked oom-killer: gfp_mask=0xd0, order=0, oom_score_adj=0
[Thu Nov 1 15:15:27 2018] tr cpuset=step_0 mems_allowed=0-1
[Thu Nov 1 15:15:27 2018] CPU: 27 PID: 33591 Comm: tr Tainted: G OE ------------ 3.10.0-693.21.1.el7.x86_64 #1
[Thu Nov 1 15:15:27 2018] Hardware name: Dell Inc. PowerEdge M630/0R10KJ, BIOS 2.5.4 08/17/2017
[Thu Nov 1 15:15:27 2018] Call Trace:
[Thu Nov 1 15:15:27 2018] [<ffffffff816ae7c8>] dump_stack+0x19/0x1b
[Thu Nov 1 15:15:27 2018] [<ffffffff816a9b90>] dump_header+0x90/0x229
[Thu Nov 1 15:15:27 2018] [<ffffffff810c7c82>] ? default_wake_function+0x12/0x20
[Thu Nov 1 15:15:27 2018] [<ffffffff8118a3d6>] ? find_lock_task_mm+0x56/0xc0
[Thu Nov 1 15:15:27 2018] [<ffffffff811f5fb8>] ? try_get_mem_cgroup_from_mm+0x28/0x60
[Thu Nov 1 15:15:27 2018] [<ffffffff8118a884>] oom_kill_process+0x254/0x3d0
[Thu Nov 1 15:15:27 2018] [<ffffffff811f9cd6>] mem_cgroup_oom_synchronize+0x546/0x570
[Thu Nov 1 15:15:27 2018] [<ffffffff811f9150>] ? mem_cgroup_charge_common+0xc0/0xc0
[Thu Nov 1 15:15:27 2018] [<ffffffff8118b114>] pagefault_out_of_memory+0x14/0x90
[Thu Nov 1 15:15:27 2018] [<ffffffff816a7f2e>] mm_fault_error+0x68/0x12b
[Thu Nov 1 15:15:27 2018] [<ffffffff816bb741>] __do_page_fault+0x391/0x450
[Thu Nov 1 15:15:27 2018] [<ffffffff816bb835>] do_page_fault+0x35/0x90
[Thu Nov 1 15:15:27 2018] [<ffffffff816b7768>] page_fault+0x28/0x30
[Thu Nov 1 15:15:27 2018] Task in /slurm/uid_11122/job_58003653/step_0 killed as a result of limit of /slurm/uid_11122/job_58003653
[Thu Nov 1 15:15:27 2018] memory: usage 8388608kB, limit 8388608kB, failcnt 3673
[Thu Nov 1 15:15:27 2018] memory+swap: usage 8388608kB, limit 16777216kB, failcnt 0
[Thu Nov 1 15:15:27 2018] kmem: usage 0kB, limit 9007199254740988kB, failcnt 0
[Thu Nov 1 15:15:27 2018] Memory cgroup stats for /slurm/uid_11122/job_58003653: cache:0KB rss:0KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
[Thu Nov 1 15:15:27 2018] Memory cgroup stats for /slurm/uid_11122/job_58003653/step_extern: cache:0KB rss:0KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
[Thu Nov 1 15:15:27 2018] Memory cgroup stats for /slurm/uid_11122/job_58003653/step_batch: cache:0KB rss:4452KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:4452KB inactive_file:0KB active_file:0KB unevictable:0KB
[Thu Nov 1 15:15:27 2018] Memory cgroup stats for /slurm/uid_11122/job_58003653/step_0: cache:6399032KB rss:1985124KB rss_huge:1476608KB mapped_file:20232KB swap:0KB inactive_anon:1890552KB active_anon:6491116KB inactive_file:1216KB active_file:892KB unevictable:0KB
[Thu Nov 1 15:15:27 2018] [ pid ] uid tgid total_vm rss nr_ptes swapents oom_score_adj name
[Thu Nov 1 15:15:27 2018] [20087] 11122 20087 28321 420 12 0 0 bash
[Thu Nov 1 15:15:27 2018] [33058] 11122 33058 63274 1357 31 0 0 srun
[Thu Nov 1 15:15:27 2018] [33060] 11122 33060 12085 207 23 0 0 srun
[Thu Nov 1 15:15:27 2018] [33073] 11122 33073 2416 406 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33153] 11122 33153 3735255 498759 1385 0 0 java
[Thu Nov 1 15:15:27 2018] [42230] 11122 42230 2542 422 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42240] 11122 42240 2543 421 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42261] 11122 42261 2542 421 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42285] 11122 42285 2541 422 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42302] 11122 42302 2543 422 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42316] 11122 42316 2542 422 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42331] 11122 42331 2564 424 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [42359] 11122 42359 2544 421 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33529] 11122 33529 2148 167 10 0 0 timeout
[Thu Nov 1 15:15:27 2018] [33538] 11122 33538 1078 88 7 0 0 time_bin
[Thu Nov 1 15:15:27 2018] [33540] 11122 33540 2148 167 10 0 0 timeout
[Thu Nov 1 15:15:27 2018] [33541] 11122 33541 2148 166 10 0 0 timeout
[Thu Nov 1 15:15:27 2018] [33542] 11122 33542 1609 177 8 0 0 ng
[Thu Nov 1 15:15:27 2018] [33543] 11122 33543 1090 89 8 0 0 tail
[Thu Nov 1 15:15:27 2018] [33544] 11122 33544 2472 181 11 0 0 awk
[Thu Nov 1 15:15:27 2018] [33546] 11122 33546 1078 88 8 0 0 time_bin
[Thu Nov 1 15:15:27 2018] [33554] 11122 33554 1078 88 8 0 0 time_bin
[Thu Nov 1 15:15:27 2018] [33556] 11122 33556 1609 177 10 0 0 ng
[Thu Nov 1 15:15:27 2018] [33562] 11122 33562 1609 177 9 0 0 ng
[Thu Nov 1 15:15:27 2018] [33570] 11122 33570 9084 299 18 0 0 tar
[Thu Nov 1 15:15:27 2018] [33586] 11122 33586 2564 333 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33587] 11122 33587 2148 166 10 0 0 timeout
[Thu Nov 1 15:15:27 2018] [33588] 11122 33588 2564 279 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33589] 11122 33589 1078 89 8 0 0 time_bin
[Thu Nov 1 15:15:27 2018] [33590] 11122 33590 2472 181 10 0 0 awk
[Thu Nov 1 15:15:27 2018] [33591] 11122 33591 1075 48 6 0 0 tr
[Thu Nov 1 15:15:27 2018] [33592] 11122 33592 2564 243 8 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33593] 11122 33593 2542 330 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33594] 11122 33594 1609 177 9 0 0 ng
[Thu Nov 1 15:15:27 2018] [33595] 11122 33595 2542 318 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33596] 11122 33596 2542 240 8 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33597] 11122 33597 2542 240 9 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33598] 11122 33598 2542 240 8 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33599] 11122 33599 2542 240 8 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] [33600] 11122 33600 2542 240 8 0 0 one-step.sh
[Thu Nov 1 15:15:27 2018] Memory cgroup out of memory: Kill process 33576 (java) score 238 or sacrifice child
[Thu Nov 1 15:15:27 2018] Killed process 33153 (java) total-vm:14941020kB, anon-rss:1973844kB, file-rss:1008kB, shmem-rss:20184kB
[Thu Nov 1 03:40:17 2018] obabel invoked oom-killer: gfp_mask=0xd0, order=0, oom_score_adj=0
[Thu Nov 1 03:40:17 2018] obabel cpuset=step_0 mems_allowed=0-1
[Thu Nov 1 03:40:17 2018] CPU: 29 PID: 123601 Comm: obabel Tainted: G OE ------------ T 3.10.0-693.21.1.el7.x86_64 #1
[Thu Nov 1 03:40:17 2018] Hardware name: Dell Inc. PowerEdge M630/0R10KJ, BIOS 2.5.4 08/17/2017
[Thu Nov 1 03:40:17 2018] Call Trace:
[Thu Nov 1 03:40:17 2018] [<ffffffff816ae7c8>] dump_stack+0x19/0x1b
[Thu Nov 1 03:40:17 2018] [<ffffffff816a9b90>] dump_header+0x90/0x229
[Thu Nov 1 03:40:17 2018] [<ffffffff810c7c82>] ? default_wake_function+0x12/0x20
[Thu Nov 1 03:40:17 2018] [<ffffffff8118a3d6>] ? find_lock_task_mm+0x56/0xc0
[Thu Nov 1 03:40:17 2018] [<ffffffff811f5fb8>] ? try_get_mem_cgroup_from_mm+0x28/0x60
[Thu Nov 1 03:40:17 2018] [<ffffffff8118a884>] oom_kill_process+0x254/0x3d0
[Thu Nov 1 03:40:17 2018] [<ffffffff811f9cd6>] mem_cgroup_oom_synchronize+0x546/0x570
[Thu Nov 1 03:40:17 2018] [<ffffffff811f9150>] ? mem_cgroup_charge_common+0xc0/0xc0
[Thu Nov 1 03:40:17 2018] [<ffffffff8118b114>] pagefault_out_of_memory+0x14/0x90
[Thu Nov 1 03:40:17 2018] [<ffffffff816a7f2e>] mm_fault_error+0x68/0x12b
[Thu Nov 1 03:40:17 2018] [<ffffffff816bb741>] __do_page_fault+0x391/0x450
[Thu Nov 1 03:40:17 2018] [<ffffffff816bb835>] do_page_fault+0x35/0x90
[Thu Nov 1 03:40:17 2018] [<ffffffff816b7768>] page_fault+0x28/0x30
[Thu Nov 1 03:40:17 2018] Task in /slurm/uid_11122/job_57832937/step_0 killed as a result of limit of /slurm/uid_11122/job_57832937
[Thu Nov 1 03:40:17 2018] memory: usage 8388608kB, limit 8388608kB, failcnt 363061
[Thu Nov 1 03:40:17 2018] memory+swap: usage 8388608kB, limit 16777216kB, failcnt 0
[Thu Nov 1 03:40:17 2018] kmem: usage 0kB, limit 9007199254740988kB, failcnt 0
[Thu Nov 1 03:40:17 2018] Memory cgroup stats for /slurm/uid_11122/job_57832937: cache:0KB rss:0KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
[Thu Nov 1 03:40:17 2018] Memory cgroup stats for /slurm/uid_11122/job_57832937/step_extern: cache:152KB rss:3944KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:3936KB inactive_file:76KB active_file:76KB unevictable:0KB
[Thu Nov 1 03:40:17 2018] Memory cgroup stats for /slurm/uid_11122/job_57832937/step_batch: cache:0KB rss:4760KB rss_huge:0KB mapped_file:0KB swap:0KB inactive_anon:0KB active_anon:4760KB inactive_file:0KB active_file:0KB unevictable:0KB
[Thu Nov 1 03:40:17 2018] Memory cgroup stats for /slurm/uid_11122/job_57832937/step_0: cache:6554284KB rss:1825468KB rss_huge:401408KB mapped_file:13556KB swap:0KB inactive_anon:439516KB active_anon:7937116KB inactive_file:1500KB active_file:1476KB unevictable:0KB
[Thu Nov 1 03:40:17 2018] [ pid ] uid tgid total_vm rss nr_ptes swapents oom_score_adj name
[Thu Nov 1 03:40:17 2018] [127018] 11122 127018 28354 476 12 0 0 bash
[Thu Nov 1 03:40:17 2018] [139355] 11122 139355 63280 1372 33 0 0 srun
[Thu Nov 1 03:40:17 2018] [139357] 11122 139357 12091 215 25 0 0 srun
[Thu Nov 1 03:40:17 2018] [139370] 11122 139370 2419 422 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139443] 11122 139443 2155734 412939 953 0 0 java
[Thu Nov 1 03:40:17 2018] [139473] 11122 139473 2564 432 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139477] 11122 139477 2563 432 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139485] 11122 139485 2550 422 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139508] 11122 139508 2563 434 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139526] 11122 139526 2572 435 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139539] 11122 139539 2573 426 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139558] 11122 139558 2563 431 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [139585] 11122 139585 2563 431 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [21062] 11122 21062 32157 931 14 0 0 bash
[Thu Nov 1 03:40:17 2018] [91238] 11122 91238 2151 170 10 0 0 timeout
[Thu Nov 1 03:40:17 2018] [91239] 11122 91239 1081 88 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [91240] 11122 91240 1612 180 9 0 0 ng
[Thu Nov 1 03:40:17 2018] [104964] 11122 104964 2151 171 10 0 0 timeout
[Thu Nov 1 03:40:17 2018] [104969] 11122 104969 1081 88 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [104975] 11122 104975 1612 181 8 0 0 ng
[Thu Nov 1 03:40:17 2018] [123586] 11122 123586 2550 374 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [123592] 11122 123592 2151 171 10 0 0 timeout
[Thu Nov 1 03:40:17 2018] [123593] 11122 123593 3325 171 12 0 0 sed
[Thu Nov 1 03:40:17 2018] [123596] 11122 123596 1081 89 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [123601] 11122 123601 130767 40835 261 0 0 obabel
[Thu Nov 1 03:40:17 2018] [125363] 11122 125363 2573 377 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [125369] 11122 125369 2151 171 10 0 0 timeout
[Thu Nov 1 03:40:17 2018] [125372] 11122 125372 1089 81 8 0 0 uniq
[Thu Nov 1 03:40:17 2018] [125373] 11122 125373 3324 171 11 0 0 sed
[Thu Nov 1 03:40:17 2018] [125380] 11122 125380 1081 88 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [125388] 11122 125388 91272 1302 179 0 0 obabel
[Thu Nov 1 03:40:17 2018] [125742] 11122 125742 2563 386 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [125743] 11122 125743 2151 170 10 0 0 timeout
[Thu Nov 1 03:40:17 2018] [125744] 11122 125744 1089 81 8 0 0 uniq
[Thu Nov 1 03:40:17 2018] [125745] 11122 125745 3324 171 12 0 0 sed
[Thu Nov 1 03:40:17 2018] [125746] 11122 125746 1081 87 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [125747] 11122 125747 91272 1309 180 0 0 obabel
[Thu Nov 1 03:40:17 2018] [125752] 11122 125752 2563 383 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [125753] 11122 125753 2151 170 9 0 0 timeout
[Thu Nov 1 03:40:17 2018] [125754] 11122 125754 1089 82 9 0 0 uniq
[Thu Nov 1 03:40:17 2018] [125755] 11122 125755 3324 172 11 0 0 sed
[Thu Nov 1 03:40:17 2018] [125756] 11122 125756 1081 88 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [125757] 11122 125757 91272 1309 179 0 0 obabel
[Thu Nov 1 03:40:17 2018] [125772] 11122 125772 2564 383 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [125773] 11122 125773 2151 170 10 0 0 timeout
[Thu Nov 1 03:40:17 2018] [125774] 11122 125774 1088 86 7 0 0 uniq
[Thu Nov 1 03:40:17 2018] [125775] 11122 125775 3324 172 12 0 0 sed
[Thu Nov 1 03:40:17 2018] [125776] 11122 125776 1081 88 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [125778] 11122 125778 66934 902 131 0 0 obabel
[Thu Nov 1 03:40:17 2018] [125819] 11122 125819 2563 383 10 0 0 one-step.sh
[Thu Nov 1 03:40:17 2018] [125820] 11122 125820 2151 171 11 0 0 timeout
[Thu Nov 1 03:40:17 2018] [125821] 11122 125821 1088 87 8 0 0 uniq
[Thu Nov 1 03:40:17 2018] [125822] 11122 125822 3324 172 10 0 0 sed
[Thu Nov 1 03:40:17 2018] [125823] 11122 125823 1081 88 8 0 0 time_bin
[Thu Nov 1 03:40:17 2018] [125824] 11122 125824 66934 931 132 0 0 obabel
[Thu Nov 1 03:40:17 2018] [126131] 11122 126131 40335 445 33 0 0 ps
[Thu Nov 1 03:40:17 2018] [126132] 11122 126132 26980 166 10 0 0 head
[Thu Nov 1 03:40:17 2018] [126133] 11122 126133 26990 153 10 0 0 column
[Thu Nov 1 03:40:17 2018] Memory cgroup out of memory: Kill process 125649 (NGSession 36387) score 197 or sacrifice child
[Thu Nov 1 03:40:17 2018] Killed process 139443 (java) total-vm:8622936kB, anon-rss:1637312kB, file-rss:960kB, shmem-rss:13484kB
在后台运行的java应用程序总是在最后被oom-manager杀死，因为我认为它释放了大部分内存。关于java程序，我检查了垃圾收集/GC日志文件，一切正常。另外，我对 JVM 使用了三个不同的版本，但问题似乎与此无关。
我怎样才能找出真正导致 oom-manager 终止我的程序的原因？
我不是我使用的机器的管理员，它们是 Linux 集群的计算节点。内核版本为3.10.0-693.21.1.el7.x86_64。
答案1
内存组内存不足
您需要避免填充正在运行的内存 cgroup。
/slurm/uid_11122/job_58003653/step_0 中的任务由于 /slurm/uid_11122/job_58003653 的限制而被终止
内存：使用量 8,388,608kB，限制 8,388,608kB，failcnt 3673
内存+交换：使用量 8388608kB，限制 16777216kB，failcnt 0
kmem：使用量 0kB，限制 9007199254740988kB，failcnt 0/slurm/uid_11122/job_58003653 的内存 cgroup 统计信息：cache:0KB rss:0KB rss_huge:0KBmapped_file:0KB swap:0KB inactive_anon:0KB active_anon:0KB inactive_file:0KB active_file:0KB unevictable:0KB
/slurm/uid_11122/ 的内存 cgroup 统计信息job_58003653/step_extern：缓存：0KB rss：0KB rss_huge：0KB 映射文件：0KB 交换：0KB inactive_anon：0KB active_anon：0KB inactive_file：0KB active_file：0KB 不可取消：0KB /slurm/uid_11122/job_58003653/step_batch 的内存 cgroup 统计信息：缓存：0KB rss:4452KB rss_huge:0KB 映射文件:0KB 交换:0KB inactive_anon:0KB active_anon:4452KB inactive_file:0KB active_file:0KB 不可删除:0KB /slurm/uid_11122/job_58003653/step_0 的内存 cgroup 统计信息：缓存：6,399,032KB rss：1,985,124KB rss_huge：1,476,608KB映射文件：2,0232KB 交换：0KBinactive_anon:1,890,552KB active_anon:6,491,116KB非活动文件：1,216KB 活动文件：892KB 不可删除：0KB
看起来“shmem”中有 ~ 6.4GB，这通常意味着 tmpfs。 （一些其他类型的 shmem 是 sysv IPC 共享内存，如ipcs或 memfd...所示）。结合 ~ 2GB RSS，您的 cgroup 就超过了 8.4GB 限制。消息中没有提到“shmem”，但我从“cache”和“active_anon”中显示的〜6.4GB中推断出它。
缓存 - 页缓存，包括 tmpfs (shmem)，以字节为单位
active_anon - 活动最近最少使用 (LRU) 列表上的匿名和交换缓存，包括 tmpfs (shmem)，以字节为单位
当 cgroup 超出其限制时，我们首先尝试从 cgroup 回收内存，以便为 cgroup 触及的新页面腾出空间。如果回收不成功，则会调用 OOM 例程来选择并终止 cgroup 中最庞大的任务。
https://www.kernel.org/doc/Documentation/cgroup-v1/memory.txt
控制组（通常称为 cgroup）是 Linux 内核的一项功能，它允许将进程组织成分层组，然后可以限制和监视这些组对各种类型资源的使用。内核的 cgroup 接口是通过称为 cgroupfs 的伪文件系统提供的。分组是在核心 cgroup 内核代码中实现的，而资源跟踪和限制是在一组按资源类型的子系统中实现的（记忆、CPU 等）。