Freebsd et OSS

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Un hasard m'a amené à regarder la taille du répertoire /tmp

Code :

root@nanopi-neo:/tmp # less /etc/fstab
/dev/mmcsd0s1   /boot/msdos     msdosfs rw,noatime      0 0
/dev/mmcsd0s2a  /               ufs rw,noatime          1 1
md              /tmp            mfs rw,noatime,-s50m    0 0
md              /var/log        mfs rw,noatime,-s15m    0 0
md              /var/tmp        mfs rw,noatime,-s12m    0 0

mfs : https://www.freebsd.org/cgi/man.cgi?query=mount_mfs

Une comparaison théorique entre ramfs et tmpfs

Citation :RAM disks use memory inefficiently; file data exists twice in both RAM disk memory and kernel memory, and RAM disk memory that is not being used by the file system is wasted. RAM disk memory is maintained separately from kernel memory, so that multiple memory-to-memory copies are needed to update file system data.

Tmpfs uses memory much more efficiently. It provides the speed of a RAM disk because file data is likely to be in main memory, causing a single memory-to-memory copy on access, and because all file system attributes are stored once in physical memory, no additional I/O requests are needed to maintain the file system. Instead of allocating a fixed amount of memory for exclusive use as a file system, tmpfs file system size is dynamic depending on use, allowing the system to decide the optimal use of memory.

https://www.cs.rit.edu/~vcss544/tmpfs.pdf