du / -d 1 -h
dd if=/dev/zero of=large.bin bs=1048576 count=200
du / -d 1 -h
mkfs.ext2 /dev/ram
//Linux 内核默认创建了 16 个 ramdisks。详情：http://blog.csdn.net/liangkaiming/article/details/6237537
mkdir /mnt/tmpfs //建立tmpfs子目录
mount tmpfs /mnt/tmpfs -t tmpfs//创建tmpft文件系统，详见：http://www.360doc.com/content/12/0731/08/6828497_227391810.shtml
ls /mnt/tmpfs
df
cd /mnt/tmpfs/
dd if=/dev/zero of=lagre.bin bs=1024576 count=256
这里会发现最多只能写进243M
df
发现dev/loop0 的空间太小要设大一些
free
umount /mnt/tmpfs
//太麻烦，懒得标注，你们自己看吧。
~~~~~~~~~~~~~~~~~~~~~~
zynq> umount /mnt/tmpfs
umount: can't umount /mnt/tmpfs: Device or resource busy
zynq> cd /
zynq> umount /mnt/tmpfs
zynq> free
total used free shared buffers
Mem: 498200 41588 456612 0 448
-/+ buffers: 41140 457060
0 0 0
zynq> mount tmpfs /mnt/tmpfs -t tmpfs size=350m
BusyBox v1.18.4 (2012-01-09 15:03:52 PST) multi-call binary.
Usage: mount [OPTIONS] [-o OPTS] DEVICE NODE
Mount a filesystem. Filesystem autodetection requires /proc.
Options:
-a Mount all filesystems in fstab
-f Update /etc/mtab, but don't mount
-n Don't update /etc/mtab
-r Read-only mount
-w Read-write mount (default)
-t FSTYPE Filesystem type
-O OPT Mount only filesystems with option OPT (-a only)
-o OPT:
loop Ignored (loop devices are autodetected)
[a]sync Writes are [a]synchronous
[no]atime Disable/enable updates to inode access times
[no]diratime Disable/enable atime updates to directories
[no]relatime Disable/enable atime updates relative to modification ti
me
[no]dev (Dis)allow use of special device files
[no]exec (Dis)allow use of executable files
[no]suid (Dis)allow set-user-id-root programs
[r]shared Convert [recursively] to a shared subtree
[r]slave Convert [recursively] to a slave subtree
[r]private Convert [recursively] to a private subtree
[un]bindable Make mount point [un]able to be bind mounted
bind Bind a file or directory to another location
move Relocate an existing mount point
remount Remount a mounted filesystem, changing flags
ro/rw Same as -r/-w
There are filesystem-specific -o flags.
zynq> mount tmpfs /mnt/tmpfs -t tmpfs -size=350m
mount: invalid option -- 'z'
BusyBox v1.18.4 (2012-01-09 15:03:52 PST) multi-call binary.
Usage: mount [OPTIONS] [-o OPTS] DEVICE NODE
Mount a filesystem. Filesystem autodetection requires /proc.
Options:
-a Mount all filesystems in fstab
-f Update /etc/mtab, but don't mount
-n Don't update /etc/mtab
-r Read-only mount
-w Read-write mount (default)
-t FSTYPE Filesystem type
-O OPT Mount only filesystems with option OPT (-a only)
-o OPT:
loop Ignored (loop devices are autodetected)
[a]sync Writes are [a]synchronous
[no]atime Disable/enable updates to inode access times
[no]diratime Disable/enable atime updates to directories
[no]relatime Disable/enable atime updates relative to modification ti
me
[no]dev (Dis)allow use of special device files
[no]exec (Dis)allow use of executable files
[no]suid (Dis)allow set-user-id-root programs
[r]shared Convert [recursively] to a shared subtree
[r]slave Convert [recursively] to a slave subtree
[r]private Convert [recursively] to a private subtree
[un]bindable Make mount point [un]able to be bind mounted
bind Bind a file or directory to another location
move Relocate an existing mount point
remount Remount a mounted filesystem, changing flags
ro/rw Same as -r/-w
There are filesystem-specific -o flags.
zynq> mount tmpfs /mnt/tmpfs -t tmpfs --size=350m
zynq> free
total used free shared buffers
Mem: 498200 41340 456860 0 448
-/+ buffers: 40892 457308
Swap 0 0 0
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 358400 0 358400 0% /mnt/tmpfs
zynq> umount /mnt/tmpfs
zynq> mount tmpfs /mnt/tmpfs -t tmpfs --size=450m
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 0 460800 0% /mn[0;31mzynq>
zynq> cd /mnt/tmpfs
zynq> ls
zynq> dd if=/dev/zero of=lagre.bin bs=1024576 count=300
300+0 records in
300+0 records out
307372800 bytes (293.1MB) copied, 0.928720 seconds, 315.6MB/s
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
zynq> dd if=/dev/zero of=lagre.bin bs=1024576 count=450
450+0 records in
450+0 records out
461059200 bytes (439.7MB) copied, 1.531221 seconds, 287.2MB/s
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 0 249100 0% /tmp
/dev/loop0 460800 450256 10544 98% /mnt/tmpfs
zynq> dd if=/dev/zero of=lagre.bin bs=1024576 count=460
460+0 records in
460+0 records out
471304960 bytes (449.5MB) copied, 1.670316 seconds, 269.1MB/s
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
p0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /m
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq[m df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> ddf
-/bin/ash: ddf: not found
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /m
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
31mzynq> d 460800 460260 540 100% /mnt/tmpfs
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq>
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq>
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq> f
-/bin/ash: f: not found
zynq> d
-/bin/ash: d: not found
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 4 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
nq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs[0;31mzynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mntzynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmp[0;31mzynq>
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tm;31mzynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tm;31mzynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 249100 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpf[0;31mzynq>
zynq>
zynq> df
Filesystem 1K-blocks Used Available Use% Mounted on
none 0 249100 0% /tmp
/dev/loop0 460800 460260 540 100% /mnt/tmpfs
zynq> df