Linux开发心得总结14 - Red Hat Linux Deployment Guide
2012-03-08 11:51
309 查看
http://www.centos.org/docs/5/html/5.2/Deployment_Guide/index.html
3.2.19.
This is one of the more commonly used files in the
The following sample
Much of the information here is used by the
This statistic only appears on the x86, Itanium, and AMD64 architectures.
architectures, the default is 262144 KB. This statistic only appears on the x86, Itanium, and AMD64 architectures.
3.2.19. /proc/meminfo
This is one of the more commonly used files in the /proc/directory, as it reports a large amount of valuable information about the systems RAM usage.
The following sample
/proc/meminfovirtual file is from a system with 256 MB of RAM and 512 MB of swap space:
MemTotal: 255908 kB MemFree: 69936 kB Buffers: 15812 kB Cached: 115124 kB SwapCached: 0 kB Active: 92700 kB Inactive: 63792 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 255908 kB LowFree: 69936 kB SwapTotal: 524280 kB SwapFree: 524280 kB Dirty: 4 kB Writeback: 0 kB Mapped: 42236 kB Slab: 25912 kB Committed_AS: 118680 kB PageTables: 1236 kB VmallocTotal: 3874808 kB VmallocUsed: 1416 kB VmallocChunk: 3872908 kB HugePages_Total: 0 HugePages_Free: 0 Hugepagesize: 4096 kB
Much of the information here is used by the
free,
top, and
pscommands. In fact, the output of the
freecommand is similar in appearance to the contents and structure of
/proc/meminfo. But by looking directly at
/proc/meminfo, more details are revealed:
MemTotal— Total amount of physical RAM, in kilobytes.
MemFree— The amount of physical RAM, in kilobytes, left unused by the system.
Buffers— The amount of physical RAM, in kilobytes, used for file buffers.
Cached— The amount of physical RAM, in kilobytes, used as cache memory.
SwapCached— The amount of swap, in kilobytes, used as cache memory.
Active— The total amount of buffer or page cache memory, in kilobytes, that is in active use. This is memory that has been recently used and is usually not reclaimed for other purposes.
Inactive— The total amount of buffer or page cache memory, in kilobytes, that are free and available. This is memory that has not been recently used and can be reclaimed for other purposes.
HighTotaland
HighFree— The total and free amount of memory, in kilobytes, that is not directly mapped into kernel space. The
HighTotalvalue can vary based on the type of kernel used.
LowTotaland
LowFree— The total and free amount of memory, in kilobytes, that is directly mapped into kernel space. The
LowTotalvalue can vary based on the type of kernel used.
SwapTotal— The total amount of swap available, in kilobytes.
SwapFree— The total amount of swap free, in kilobytes.
Dirty— The total amount of memory, in kilobytes, waiting to be written back to the disk.
Writeback— The total amount of memory, in kilobytes, actively being written back to the disk.
Mapped— The total amount of memory, in kilobytes, which have been used to map devices, files, or libraries using the
mmapcommand.
Slab— The total amount of memory, in kilobytes, used by the kernel to cache data structures for its own use.
Committed_AS— The total amount of memory, in kilobytes, estimated to complete the workload. This value represents the worst case scenario value, and also includes swap memory.
PageTables— The total amount of memory, in kilobytes, dedicated to the lowest page table level.
VMallocTotal— The total amount of memory, in kilobytes, of total allocated virtual address space.
VMallocUsed— The total amount of memory, in kilobytes, of used virtual address space.
VMallocChunk— The largest contiguous block of memory, in kilobytes, of available virtual address space.
HugePages_Total— The total number of hugepages for the system. The number is derived by dividing
Hugepagesizeby the megabytes set aside for hugepages specified in
/proc/sys/vm/hugetlb_pool.
This statistic only appears on the x86, Itanium, and AMD64 architectures.
HugePages_Free— The total number of hugepages available for the system.This statistic only appears on the x86, Itanium, and AMD64 architectures.
Hugepagesize— The size for each hugepages unit in kilobytes. By default, the value is 4096 KB on uniprocessor kernels for 32 bit architectures. For SMP, hugemem kernels, and AMD64, the default is 2048 KB. For Itanium
architectures, the default is 262144 KB. This statistic only appears on the x86, Itanium, and AMD64 architectures.
相关文章推荐
- Linux开发心得总结14 - linux情景分析--存储管理
- Red Hat Linux 9 安装心得
- Linux开发心得总结16 - linux 程序加载过程
- Linux开发心得总结2 - 频繁分配释放内存导致的性能问题的分析
- Linux开发心得总结20 - 内核编程中的全局变量使用(EXPORT_SYMBOL())
- Linux开发心得总结3 - brk和sbrk及内存分配函数介绍
- 开发环境搭建1:Red_Hat_linux的安装时的注意事项
- 红帽为开发订阅成员提供免费的Red Hat Enterprise Linux
- Linux开发心得总结4 - 在内核中添加系统调用
- Linux开发心得总结5 - Linux下OOM Killer机制详解
- Linux运维笔记-文档总结-自动安装 RED HAT ENTERPRISE LINUX
- Linux开发心得总结6 - When Linux Runs Out of Memory
- 2-4-RHEL6.3搭建samba服务器案例分析与总结(Red Hat Enterprise Linux Server6.3)@树袋飘零
- 用Red Hat Enterprise Linux 搭建Java开发环境
- 2-6-RHEL6.5搭建vsftpd服务器案例分析与总结(Red Hat Enterprise Linux Server6.3)@树袋飘零
- Linux开发心得总结15 - Learning about Linux Processes
- Linux开发心得总结17 - Linux程序数据段分布分析
- Red Hat Linux 6.2 Memcached安装总结