eMMC and SD cards are almost the same as Gerald said. eMMC is based on MLC NAND
MLC NAND enables around 10k write cycles SLC NAND enables more than 100k write cycles. That is why we use only SLC in our industrial products. I'm sure when you supply products with 5 year warranty you don't want to discuss "eMMC/MLC reliability". Less risks - less profit lost. 2014-05-22 11:13 GMT+04:00 Willem Buitendyk <[email protected]>: > I wasn't seeing data corruption due to Linux but from the cards going > completely kaput. No amount of effort seemed to restore them. I was under > the impression the eMMC used MLC rather than TLC or MBC? That would imply > a different controller and ideally a much longer lifespan. > > > > On Wednesday, May 21, 2014 12:27:28 PM UTC-7, Gerald wrote: > >> Reliability at the cell level is the exactly the same. he controller is >> exactly the same. >> >> However, having more unused space enhances the wear leveling where cells >> get used less often. >> >> It does not however prevent issues with data corruption for any Linux >> issues. >> >> Gerald >> >> >> >> >> >> On Wed, May 21, 2014 at 2:21 PM, Willem Buitendyk <[email protected]>wrote: >> >>> I have about 150 beaglebone's running wild over a large geographical >>> area, basically all over British Columbia. When I first deployed them last >>> year they all started failing within about a month. That amounted to a lot >>> of needless driving, hair pulling, forehead banging and just general over >>> anxiety - its a wonder I'm still alive. >>> >>> I eventually ended up using two uSD cards, one with a read only mounted >>> filesystem and the other used for writing data (ext4). My beaglebone's are >>> paired with a msp430 so I have managed to ensure they also receive a nice, >>> clean power down. So far its been about a year and I'd say well over 95% >>> are still working fine. However, I recently talked with a tech support >>> from an industrial SD card manufacturer and he informed me that SD cards >>> that are only ever read to can also fail eventually. He suggested that you >>> write a little bit once in a while to activate the wear levelling >>> mechanism. As things seem to be working (for now) I haven't drummed up the >>> courage to try writing again. >>> >>> Now we have the beaglebone black with 4G eMMC and I'm wondering just how >>> much more reliable eMMC is compared to the stock Kingston 4GB cards in read >>> only mode that came with the Beaglebone. I know eMMC is supposed to be >>> much improved having an integrated controller but wonder if in a read-only >>> scenario it makes any difference? Furthermore, I wonder if others on here >>> can offer any experiences or comparisons of eMMC to say SLC memory? >>> >>> Thanks >>> >>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- LinkedIn - http://www.linkedin.com/in/maximpodbereznyy Company - http://www.linkedin.com/company/mentorel Facebook - https://www.facebook.com/mentorel.company -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
