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59

If you worry about write cycles, you won't get anywhere. You will have data on your SSD that changes frequently; your home, your configs, your browser caches, maybe even databases (if you use any). They all should be on SSD: why else would you have one, if not to gain speed for the things you do frequently? The number of writes may be limited, but a modern ...


21

Ok, so the goal is to get as much bang for the buck as possible - Speed vs. the price of replacement hardware (assuming a single large harddisk and medium-size SSD, which seems to be the norm). To simplify you can to weigh how much you notice the speed increase from moving a file to the SSD against the number of sectors written to move that file to the SSD. ...


9

"Low level formatting" was done on floppies, where you could write at different densities by choosing to organize the tracks and sectors differently. But this makes no sense for most modern media. Its notion of how to organize the data on the device is fixed and unchangeable. It doesn't make any sense at all for flash, which has discrete bits, rather than ...


6

Using sgdisk You can use sgdisk to print detailled information: sgdisk --print <device> […] Disk /dev/sdb: 15691776 sectors, 7.5 GiB Logical sector size: 512 bytes […] When you multiply the number of sectors with the sector size you get the exact byte count that should match the output of dd. Using /sys directly You can also get those numbers ...


5

No, you should not be required to format the CF card before installing Linux. The Syba adapter should present the CF storage to the computer as a fully-writable SATA drive, and should thus allow the Linux installer to partition and format it. The fact that the installer cannot write to the CF leads me to suspect that at least one of a few things could be ...


5

There is a new dm target called "snapshot-merge". If you format your USB flash memory as a LVM physical volume, and then locate your desired filesystem atop it in a logical volume, you can Activate a volume group containing your USB flash memory and another LVM physical volume on a local disk. Create a snapshot of the logical volume on the local disk. ...


5

Low-level formatting means many different things to different people and on different contexts. The original meaning was a step needed in the formatting of disks - disk drives need header, sync and other patterns written on the media before it can store data to it. In this way the head can detect when it is A) on a track and B) where it is on the track. ...


5

You generally don't want to write the filesystem on the entire block device (ie. /dev/sdd), you want to create a partition and then put the filesystem in there (ie. /dev/sdd1). That is also what your mkfs complained about. If you are sure you only want to have one filesystem on this disk at a time, and you don't need a bootloader, you can safely ignore this ...


4

There is no way to do a low-level format on most flash devices, since they have an additional translation layer from USB/ATA/SD/etc. to MTD which obscures the low-level MTD devices (which can be low-level formatted if gotten to directly [which you can't]).


4

use dd command for this dd if=/dev/zero of=/dev/hda This will destroy ALL data on the hard drive, all boot sector info and all data on all partitions. It will not however render the disk useless, you simply have a clean disk that only needs to have partitions created and a new boot sector installed, which will happen when you install any OS including Linux ...


4

Was the name of the device U167CONTROLLER before? It may be that the microcontroller on the device has encountered some abnormal condition (totally possible with less than totally reputable manufacturers) and needs to be reprogrammed. This is a bit of a black art and it's likely you will only find Windows programs that can reprogram the microcontroller. ...


3

The tilde expands to "$HOME", so when you write ~/Users/Gurpreet/Desktop/target.img what you've really written is /Users/Gurpreet/Users/Gurpreet/Desktop/target.img. Just get rid of the redundancy and write one (the tilde) or the other (/Users/Gurpreet).


3

The mount command has two related options: sync All I/O to the filesystem should be done synchronously. dirsync All directory updates within the filesystem should be done synchronously. You can specify them in the mount command's -o option: mount -o sync /mnt/flashdrive Or in your /etc/fstab's fourth column: /dev/sdb1 /mnt/flashdrive ...


3

Your looking for a distribution, optimized for flash disk installation? I believe the concept of flash must be expounded. As you already knew, an SSD is not directly controlled. Firmware exists, as an intermediate, which controls the physical read/write process. Additionally as you understood, SSD firmware has a multitude of longevity features included. ...


3

Btrfs uses crc32c checksums to check the integrity of blocks. If the checksum doesn't match the block when it's read then an alternative block is read. This is assuming there is an alternative (RAID1). If that block also fails or if there is no alternative an EIO (error input/output) is returned. I do not know of any way to automatically detecting errors, ...


3

The manufacturer sold you the 2GB USB stick as 2 Gigabytes, meaning 2000000000 bytes. Your computer is showing the stick in units of Gigibytes. 1 Gigibyte is 1024 x 1024 x 1024 bytes, which is 1073741824 bytes. If you divide your 2000000000 by 1073741824 you'll end up with 1.86264514923095703125 or, rounded to two decimal places 1.86 GiB. In other words, ...


2

mkfs.vfat /dev/hda1 will do the equivalent of the MSDOS "format" command.


2

Puppy Linux was originally designed for running from a USB stick, and they make it easy for you to save your files in the same device.


2

You can do this by arranging for the device to be mounted with the sync option. But it's not such a good idea, because this can wear cheap USB flash drives very fast (this has been discussed on the Linux kernel mailing list). Recent versions of Linux have the flush option for FAT filesystems, which is somewhere between sync and async: it causes all delayed ...


2

This seems a use case for dm-userspace+cowd: in essence, you would set up a DM target (block device) consisting of a COW (copy-on-write) file and the block device corresponding to your USB stick, and use it to host a filesystem. All updates would go to the COW file; reads which are not in the COW file would be served off the USB stick; after you unmount the ...


2

If we look at the source code of driver in the Linux kernel (drivers/mtd/nand/alauda.c), we see that the mtd device should be called "alauda". For example, in cmx270_nand.c mtd name is cmx270-0. In kernel log information about it, looks like: Creating 1 MTD partitions on "NAND 512MiB 3,3V 8-bit": 0x00000000-0x20000000 : "cmx270-0" Check dmesg (grep ...


2

It would be more proper to say Flash Memory has only a limited number of erase cycles, these caused eventually by writes. There are many good articles available about this distinction. When you mention burning a Linux image into router firmware, that is probably NOR flash or an EEProm. NOR is the type of flash with quicker reads, NAND the type with quicker ...


2

The /tmp and /var directories are the ones that many system programs write to a lot, and depend on being writeable. Minimizing writes to these directories, or configuring Linux to mount these directories on external storage devices that are replaceable, as opposed to on board flash, would go a long way towards accomplishing your goal. /home and swap ...


2

If the flash has a filesystem on it and you just want to open a file but bypass the cache for IO to that file, then open it with the O_DIRECT flag. If it has no filesystem on it, then you just open the block device directly.


2

Take a look at this page: http://www.ardamis.com/2009/07/02/usb-drive-unusable-unformattable-and-reporting-0-bytes-capacity/ .. interesting reading. In short, the author, running Win OS, examined a functioning USB-stick (the faulty stick and the functional one were both from Sandisk). He found a .dll file on the functional stick and a URL inside the dll ...


2

Create a third, tiny, partition to hold your data. Any other location on your disk will sooner or later bring trouble if indeed you cannot rely on the filesytems. Sometimes the last few clusters of a disk cannot be addressed in the FAT entry, that may be an option but it heavily depends on exact size of the device. Does the embedded CPU / device have ...


2

LVM does not substantially change the number of reads or writes. (Total change is zero in most cases, since all it does is translate some numbers in the write command and pass them down.)


2

Passing expert on the installer command line will tell it to enable installing to devices other than internal drives.


2

This refers to the mode the device was in when the data was collected. From the man page: Some SMART attribute values are updated only during off-line data collection activities; the rest are updated during normal operation of the device or during both normal operation and off-line testing. The Attribute value table produced by the '-A' option indicates ...


2

A couple of ways: If you can get SMART data from an SD cart with smartctl, it may have a bytes written counter (no idea if this is possible). This will be the most accurate, as it will count all partitions and also not be lost over reboot. It may also be able to count any write-amplification caused by erase block size and/or wear-leveling. Depending on the ...



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