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Special Forums Hardware Filesystems, Disks and Memory Does vmstat -d give a count of actual physical writes/reads done to/from hard disk? Post 302315150 by otheus on Monday 11th of May 2009 04:39:14 PM
Old 05-11-2009
Well, if you're using Linux, you can look at the sysstat code, which probably does some kind of ioctl on the raw device, and so you could look at the Linux kernel, which might end up telling you that it counts the number of blocks sent to the IO controller for writing; whether or not that means the device actually wrote those blocks, I don't think one can say.

Now it could be that the disk and its controller keep track of a statistic and it's possible to get that value, but I doubt this is what sa/sysstat relies on. Further, I've written SCSI drivers before, and if this feature exists nowadays, it's not in the standard, meaning it's on a device-by-device basis.
 

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MKFS.MINIX(8)						       System Administration						     MKFS.MINIX(8)

NAME
mkfs.minix - make a Minix filesystem SYNOPSIS
mkfs.minix [options] device [size-in-blocks] DESCRIPTION
mkfs.minix creates a Linux MINIX filesystem on a device (usually a disk partition). The device is usually of the following form: /dev/hda[1-8] (IDE disk 1) /dev/hdb[1-8] (IDE disk 2) /dev/sda[1-8] (SCSI disk 1) /dev/sdb[1-8] (SCSI disk 2) The device may be a block device or a image file of one, but this is not enforced. Expect not much fun on a character device :-). The size-in-blocks parameter is the desired size of the file system, in blocks. It is present only for backwards compatibility. If omit- ted the size will be determined automatically. Only block counts strictly greater than 10 and strictly less than 65536 are allowed. OPTIONS
-c, --check Check the device for bad blocks before creating the filesystem. If any are found, the count is printed. -n, --namelength length Specify the maximum length of filenames. Currently, the only allowable values are 14 and 30 for file system versions 1 and 2. Ver- sion 3 allows only value 60. The default is 30. -i, --inodes number Specify the number of inodes for the filesystem. -l, --badblocks filename Read the list of bad blocks from filename. The file has one bad-block number per line. The count of bad blocks read is printed. -1 Make a Minix version 1 filesystem. This is the default. -2, -v Make a Minix version 2 filesystem. -3 Make a Minix version 3 filesystem. -V, --version Display version information and exit. The long option cannot be combined with other options. -h, --help Display help text and exit. EXIT CODES
The exit code returned by mkfs.minix is one of the following: 0 No errors 8 Operational error 16 Usage or syntax error SEE ALSO
fsck(8), mkfs(8), reboot(8) AVAILABILITY
The mkfs.minix command is part of the util-linux package and is available from https://www.kernel.org/pub/linux/utils/util-linux/. util-linux June 2015 MKFS.MINIX(8)
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