Brandon, I'm curious as to how you calculated a lifetime of 2 yrs for the 16Gb card with 2Gb free?
On Thu, Jun 12, 2014 at 11:55 AM, Brandon I <brandon.ir...@gmail.com> wrote: > With a 16Gb card, you'll most likely get about 2 years use before the card > fails, assuming you had 2gb free on your failing cards card, the 16Gb card > has the same number of writes until failure for the memory blocks, and the > same disk activity. > > This assumes that you're have a perfect power supply that never shuts off > during a write (which will damage the memory cells) or unflushed operation > (which can corrupt the filesystem). > > If you're writing to flash media, it will eventually fail. :-\ Ideally, > you would have your os disk read only (read only partition doesn't > necessarily work due to sd card wear leveling controller not being aware of > partitions), and log files logged elsewhere where your software could > gracefully handle the eventual failure of the log file flash disk. Have > this log file disk easily accessible for customers to change. > > You could not flush your log file writes until some sort of failure or > buffer size, so that you're not writing whole erase blocks for a sentence > worth of log message. And, of course, turn off all the access time > capabilities with your mount options (noatime, nodiratime). > > The only solution is to reduce the number of writes each memory block is > seeing in a day, and be aware that eventual failure can't be avoided if > writing anything. > > On Thursday, June 12, 2014 7:24:14 AM UTC-7, RobertCNelson wrote: > >> On Thu, Jun 12, 2014 at 9:14 AM, Frank Talamy <tala...@gmail.com> wrote: >> > >> > Hi everyone, >> > >> > I've been using the BeagleBone Black for a while now. I got my apps >> running >> > just fine for like 2-3 months straight, not a single problem. >> > >> > OS : Debian Wheezy installed on Samsung 4GB µSD card. >> > Cross compilation platform : ELDK (armv7-hf) >> > >> > I've tested my apps on different brands of SD Cards (Kingston, samsung, >> > sandisk ...) and have killed several Kingston cards in a matter of >> days. By >> > killing, I mean the BeagleBone wasn't booting on them anymore and they >> were >> > no longer mounted when plugged via a USB-Card-reader. I had this kind >> of >> > dmesg output (the [...] here means a lot of the same 7 lines in a >> loop): >> > >> > [626903.528266] sd 11:0:0:0: [sdd] Device not ready >> > [626903.528268] sd 11:0:0:0: [sdd] Result: hostbyte=DID_OK >> > driverbyte=DRIVER_SENSE >> > [626903.528272] sd 11:0:0:0: [sdd] Sense Key : Not Ready [current] >> > [626903.528275] sd 11:0:0:0: [sdd] Add. Sense: Medium not present >> > [626903.528279] sd 11:0:0:0: [sdd] CDB: Read(10): 28 00 00 00 00 00 00 >> 00 08 >> > 00 >> > [626903.528287] end_request: I/O error, dev sdd, sector 0 >> > [626903.528290] Buffer I/O error on device sdd, logical block 0 >> > [626903.530266] sd 11:0:0:0: [sdd] Device not ready >> > [626903.530269] sd 11:0:0:0: [sdd] Result: hostbyte=DID_OK >> > driverbyte=DRIVER_SENSE >> > [626903.530272] sd 11:0:0:0: [sdd] Sense Key : Not Ready [current] >> > [626903.530275] sd 11:0:0:0: [sdd] Add. Sense: Medium not present >> > [626903.530279] sd 11:0:0:0: [sdd] CDB: Read(10): 28 00 00 00 00 00 00 >> 00 08 >> > 00 >> > [626903.530287] end_request: I/O error, dev sdd, sector 0 >> > [626903.530290] Buffer I/O error on device sdd, logical block 0 >> > [626903.532391] sd 11:0:0:0: [sdd] Device not ready >> > [626903.532393] sd 11:0:0:0: [sdd] Result: hostbyte=DID_OK >> > driverbyte=DRIVER_SENSE >> > [626903.532396] sd 11:0:0:0: [sdd] Sense Key : Not Ready [current] >> > [626903.532400] sd 11:0:0:0: [sdd] Add. Sense: Medium not present >> > [626903.532404] sd 11:0:0:0: [sdd] CDB: Read(10): 28 00 00 00 00 08 00 >> 00 08 >> > 00 >> > [626903.532412] end_request: I/O error, dev sdd, sector 8 >> > [...] >> > [626903.812724] sd 11:0:0:0: [sdd] Device not ready >> > [626903.812725] sd 11:0:0:0: [sdd] Result: hostbyte=DID_OK >> > driverbyte=DRIVER_SENSE >> > [626903.812728] sd 11:0:0:0: [sdd] Sense Key : Not Ready [current] >> > [626903.812731] sd 11:0:0:0: [sdd] Add. Sense: Medium not present >> > [626903.812734] sd 11:0:0:0: [sdd] CDB: Read(10): 28 00 00 00 00 00 00 >> 00 08 >> > 00 >> > [626903.812740] end_request: I/O error, dev sdd, sector 0 >> > [626903.814725] sd 11:0:0:0: [sdd] Device not ready >> > [626903.814728] sd 11:0:0:0: [sdd] Result: hostbyte=DID_OK >> > driverbyte=DRIVER_SENSE >> > [626903.814731] sd 11:0:0:0: [sdd] Sense Key : Not Ready [current] >> > [626903.814735] sd 11:0:0:0: [sdd] Add. Sense: Medium not present >> > [626903.814739] sd 11:0:0:0: [sdd] CDB: Read(10): 28 00 00 00 00 00 00 >> 00 08 >> > 00 >> > [626903.814747] end_request: I/O error, dev sdd, sector 0 >> > [626903.820536] sdd: detected capacity change from 3947888640 to 0 >> > >> > >> > That's why I chose to use Samsung sd cards instead. Everything was fine >> for >> > 2-3 whole months, but now I had one of my systems getting the exact >> same >> > symptoms as when using the Kingston cards. >> > >> > Did anyone experience this kind of problem using his beagle bone so far >> ? >> > Does anyone have an idea of something that could damage the SD card so >> much >> > which is or isn't directly related to the use of a beagle bone black >> (Heat, >> > compulsive logging, ...) ? >> > Can anyone suggest a brand that has solid and enduring SD Cards for an >> app >> > that is logging quite regularly ? >> >> I use SanDisk Ultra's 16GB's on my bbw & bbb's on my gcc testing farm. >> Those microSD's have been running fine for almost a year now, under >> 100% load for 24/7 bulding/testing gcc stable branches. (lots of file >> deletions/creations). Previously to that i had been running SanDisk >> Ultra's 8GB variants, but starting with gcc-4_8-branch i began to run >> out of build space. >> >> http://rcn-ee.homeip.net:81/dl/gcc/archive/20140610-11:24- >> gitb28747e-gcc-4_9-branch-am335x-boneblack-512mb-1/ >> >> Regards, >> >> -- >> Robert Nelson >> http://www.rcn-ee.com/ >> > -- > 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 beagleboard+unsubscr...@googlegroups.com. > 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 beagleboard+unsubscr...@googlegroups.com. 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