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For instance, Raspberry PI managed to destroy SD card in few weeks. (It seems to be a common problem.) However, internal storage in a smartphone works well for several years (5-years-old Nexus One is still working well). Is the internal storage made by different technology?

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    \$\begingroup\$ Smart phones usually aren't writing to SD cards like they're RAM. \$\endgroup\$ – Samuel Jun 11 '15 at 20:24
  • \$\begingroup\$ @Samuel RPi does? \$\endgroup\$ – Eugene Sh. Jun 11 '15 at 20:29
  • \$\begingroup\$ @EugeneSh. Depending on the OS, it's used for as a swap space because the on board memory is rather small. \$\endgroup\$ – Samuel Jun 11 '15 at 20:40
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Is the internal storage made by different technology?

No, it is often just embedded MMC - which is technically equal to a SD card, just in a BGA package for soldering onto a PCB.

Note that there are very bad quality SD cards on the market, which do not tolerate much writing. I managed to break two el cheapo noname cards in weeks, without writing that much data with my microcontroller.

Using SWAP on SD will break even good cards with wear leveling rather quickly. Flash memory allows only a limited amount of write cycles, and swapping can cause a lot of writes.

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There is 2 types of flash memory technology, NOR flash and NAND flash. NAND flash is usually used for SD cards because its cheaper, higher density but less reliable. NOR is less dense, expensive and more reliable. Phones and tables use DiskonChip technology that is NAND based but has extra logic to deal with the short comings of NAND flash. For more read info this white paper I wonder if the raspberry PI doesn't implement a very good wear leveling scheme to avoid the SD cards from failing

NOTE: The attached white paper dates back to '02 so the densities stated are low compare to today's standards

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  • \$\begingroup\$ The SD card is supposed to do wear leveling itself internally. \$\endgroup\$ – Turbo J Jun 11 '15 at 21:19
  • \$\begingroup\$ The Raspberry Pi would not be implementing any wear leveling scheme at all. This is left up to the SD cards (and is optional). Good name-brand SD cards (SanDisk in particular) do wear leveling; cheap generic Chinese knock-offs do not include this since it's estimated to cost 60 cents to add to a card. \$\endgroup\$ – tcrosley Jun 11 '15 at 21:22
  • \$\begingroup\$ Almost all SD cards do some sort of wear leveling and bad block management, because you can use cheaper untested flash memory when you do. \$\endgroup\$ – Turbo J Jun 11 '15 at 21:52

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