TMPFS file system under Linux (/DEV/SHM)

Introduced

   / dev/shm/ < Span style= "font-family: ' The song Body '; > is a use of tmpfs file system is actually a special file system. redhat mkfs formatted.

Tmpfs is a memory-based Linux/unix system. Virtualfile System. TMPFS can use your memory or swap partition to store files (that is, its storage space isVirtual Memoryin, the VMbyReal Memoryand theSwapcomposition). Thus, TMPFS primarily stores staged files. It has the following 2 advantages: 1. The size of the dynamic file system. 2. TmpfsUseVMSbuilt file system, speed of course fast. 3.data loss after reboot.

When you deleteTmpfswhen the file in, Tmpfswill dynamically reduce the file system and releaseVMSResources ,LINUX The temporary files of some programs can be placed in theTmpfs, the use ofTmpfs features faster than hard drive to improve system performance . In practice, setting this file system for the specific needs of your application can improve application read-write performance, such as SquidThe cache directory is placed in the/ tmp, PHP sessionfiles are placed in/ tmp, Socketfiles are placed in/ tmp,or use/ tmpas a cache device for other applications

Temporarily modify the/DEV/SHM size

#mount-o size=1500m-o nr_inodes=1000000-o noatime,nodiratime-o remount/dev/shm

mount-t tmpfs-o size=20m tmpfs/tmp Temporary mount use

Boot-enabled configuration

can be in /etc/fstab define its size in

Tmpfs /dev/shm tmpfs,defaults,size=512m 0 0

< Span style= "FONT-SIZE:12PT;" >tmpfs                    /tmp                         tmpfs defaults,size=25m             0 0

modified after execution Mount-o Remoount/dev/shm after the effective

mkdir/dev/shm/tmp (/dev/shm/The new directory is bound to /tmp,then/ tmp uses the tmpfs file system )

chmod 1777/dev/shm/tmp

Mount--bind/dev/shm/tmp/tmp

Reference

Understanding and use of/dev/shm under Linux directory

This article is from the "Adelphos" blog, make sure to keep this source http://adelphos.blog.51cto.com/2363901/1581175

TMPFS file system under Linux (/DEV/SHM)