注意：在你跳得太快之前,是的我读了
linuxatemyram.com！
我有一个64GB RAM的服务器.
free -m说我的RAM已满,而且不是因为磁盘缓存：
total used free shared buffers cached Mem: 64458 64117 340 201 67 331 -/+ buffers/cache: 63719 739 Swap: 1532 383 1149
但是,按内存使用排序的最高值不能达到64GB：
KiB Mem: 66005116 total,65652464 used,352652 free,67512 buffers KiB Swap: 1569780 total,392656 used,1177124 free. 337464 cached Mem PID USER PR NI VIRT RES SHR S %cpu %MEM TIME+ COMMAND 6258 MysqL 20 0 38.665g 0.033t 4924 S 1.3 54.3 482:26.21 MysqLd 2293 root 20 0 165896 102116 101964 S 0.0 0.2 0:43.53 systemd-journal 4909 root 20 0 377548 57840 57548 S 0.0 0.1 0:18.47 rsyslogd 26639 www 20 0 650076 53348 32968 S 0.0 0.1 11:32.27 PHP-fpm 26640 www 20 0 648344 51912 32984 S 0.0 0.1 11:37.43 PHP-fpm 26642 www 20 0 648600 51472 32580 S 0.0 0.1 11:37.16 PHP-fpm 26669 www 20 0 648148 50696 31988 S 0.0 0.1 11:35.24 PHP-fpm 26643 www 20 0 648452 50616 31628 S 0.0 0.1 11:36.19 PHP-fpm 26641 www 20 0 648620 50496 31340 S 0.0 0.1 11:36.51 PHP-fpm 28121 www 20 0 648620 48820 29660 S 0.0 0.1 11:35.75 PHP-fpm 27231 www 20 0 647508 48804 30760 S 0.0 0.1 11:35.61 PHP-fpm 28029 www 20 0 648044 48752 30172 S 0.0 0.1 11:37.20 PHP-fpm 28117 www 20 0 647868 48700 30296 S 0.0 0.1 11:36.45 PHP-fpm 28122 www 20 0 648340 48568 29676 S 0.0 0.1 11:35.73 PHP-fpm 8569 www 20 0 649028 40268 20704 S 0.0 0.1 11:31.50 PHP-fpm 10126 www 20 0 648432 39420 20700 S 0.0 0.1 9:58.52 PHP-fpm 22386 www 20 0 647996 39400 20868 S 0.0 0.1 11:25.00 PHP-fpm 9643 www 20 0 647976 39220 20704 S 0.0 0.1 11:29.23 PHP-fpm 23077 www 20 0 647852 39084 20692 S 0.0 0.1 11:11.80 PHP-fpm 10139 www 20 0 647580 38808 20692 S 0.0 0.1 9:59.94 PHP-fpm 6326 www 20 0 647368 38396 20696 S 0.7 0.1 8:32.34 PHP-fpm 4727 www 20 0 646128 37304 20692 S 0.0 0.1 8:30.20 PHP-fpm 5459 www 20 0 645988 37156 20688 S 0.0 0.1 7:15.13 PHP-fpm 2173 www 20 0 645240 36408 20684 S 0.0 0.1 4:39.13 PHP-fpm 20752 www 20 0 644536 35428 20680 S 0.0 0.1 4:29.78 PHP-fpm 5396 www 20 0 644468 35324 20692 S 0.0 0.1 4:14.65 PHP-fpm 17558 www 20 0 642668 33816 20740 S 0.0 0.1 1:28.34 PHP-fpm 28133 www 20 0 642780 33636 20704 S 0.0 0.1 0:49.88 PHP-fpm 10925 www 20 0 479584 29264 11212 S 3.0 0.0 0:00.09 PHP 26632 root 20 0 552136 26072 19468 S 0.0 0.0 0:37.74 PHP-fpm 4946 named 20 0 697996 18748 2104 S 0.0 0.0 3:46.96 named 15609 apache 20 0 2137056 8120 1592 S 0.0 0.0 0:56.18 httpd 8584 root 20 0 133432 4864 3700 S 0.0 0.0 0:00.08 sshd
MysqL单独使用54.3％,这是完全正常的,因为它的innodb_buffer_pool_size为32G.其他进程的内存使用率大约为2.8％,总计为57.1％.
剩下的32％在哪里？
编辑：/ proc / meminfo的内容：
MemTotal: 66005116 kB MemFree: 353272 kB Buffers: 66328 kB Cached: 736620 kB SwapCached: 11348 kB Active: 34396680 kB Inactive: 2651132 kB Active(anon): 34223240 kB Inactive(anon): 2228020 kB Active(file): 173440 kB Inactive(file): 423112 kB Unevictable: 0 kB Mlocked: 0 kB SwapTotal: 1569780 kB SwapFree: 1177448 kB Dirty: 328 kB Writeback: 0 kB AnonPages: 36234364 kB Mapped: 125208 kB Shmem: 206396 kB Slab: 28058904 kB SReclaimable: 28010224 kB SUnreclaim: 48680 kB KernelStack: 2760 kB PageTables: 94780 kB NFS_Unstable: 0 kB Bounce: 0 kB WritebackTmp: 0 kB CommitLimit: 34572336 kB Committed_AS: 38572348 kB VmallocTotal: 34359738367 kB VmallocUsed: 382304 kB VmallocChunk: 34359353572 kB HardwareCorrupted: 0 kB DirectMap4k: 9000 kB DirectMap2M: 2054144 kB DirectMap1G: 67108864 kB
slabtop的输出：
Active / Total Objects (% used) : 147380425 / 147413026 (100.0%) Active / Total Slabs (% used) : 7005839 / 7005839 (100.0%) Active / Total Caches (% used) : 71 / 144 (49.3%) Active / Total Size (% used) : 27615020.12K / 27627490.91K (100.0%) Minimum / Average / Maximum Object : 0.01K / 0.19K / 16.12K OBJS ACTIVE USE OBJ SIZE SLABS OBJ/SLAB CACHE SIZE NAME 146851887 146851887 12% 0.19K 6992947 21 27971788K dentry 124936 124936 100% 0.07K 2231 56 8924K Acpi-ParseExt 105144 105144 100% 0.10K 2696 39 10784K buffer_head 49920 49172 98% 0.06K 780 64 3120K kmalloc-64 29916 29916 100% 0.11K 831 36 3324K sysfs_dir_cache 29856 29661 99% 0.12K 933 32 3732K kmalloc-128 21450 21128 98% 0.18K 975 22 3900K vm_area_struct 19328 19328 100% 0.03K 151 128 604K kmalloc-32 18258 13383 73% 0.93K 537 34 17184K ext4_inode_cache 17952 11651 64% 0.04K 176 102 704K ext4_extent_status 16828 6513 38% 0.55K 601 28 9616K radix_tree_node 14400 13996 97% 0.06K 225 64 900K anon_vma 11645 7903 67% 0.05K 137 85 548K shared_policy_node 10710 7006 65% 0.19K 510 21 2040K kmalloc-192 10608 10608 100% 0.04K 104 102 416K Acpi-Namespace 9728 9728 100% 0.01K 19 512 76K kmalloc-8 ...
