[Music] welcome to another video from explaining computers.com this time I'm going to talk about the life expectancy of different storage media including hard drives ssds and Optical discs this is a subject I'm frequently being asked to about so let's go and get started here we have a selection of magnetic solid state and optical storage media in optimal conditions data stored on magnetic media can last several decades with taped cartridges having up to a 30-year lifespan however the average life expectancy of a hard drive is generally reported to be between 3 7even years in typical use
the life expectancy of solid state storage depends on the type of fash memory cells on which it's based and how many times they've been Rewritten but as a Rough Guide modern branded ssds should last at least 5 to 10 years in typical use this noted data may be lost after a year or two if the SSD is left unpowered finally when it comes to writable optical storage some highquality media can retain data for several decades however it's also not uncommon for lowquality media to be unusable after a couple of years as you may gather it's
incredibly difficult to predict the exact life expectancy of any particular kind of digital media not least this is because it depends on the type and intensity of use environmental conditions and any time spent in long-term storage this video is there therefore based on the best information I can find with many references included in the video description it's also important to keep in mind that any average life expectancy figure lies at the middle of a normal statistical distribution I note this because when I published a video about SSD life expectancy some people commented that the average
figures I gave were wrong because they owned a drive that had lasted for a far longer or shorter period and so we must remember that an average figure does not become invalid due to an occasional outlier such as a drive with a factory defect that fails after a few days weeks or months hard drives read and write data to spinning magnetic platters using heads that float just above their surface the heads are moved between tracks by actuator arms and the fact this all works so relia ly it's amazing generally the death of a hard drive
is due to the failure of a mechanical part such as a motor or a scratch on a drive platter caused by a head crushing into its surface however the circuit board controller in a hard drive may also fail for example following a power surge so how long will a hard drive last well the two largest manufacturers Seagate and Western Digital are for warranties of 2 years on entry level models rising to 5 years on higher end and Enterprise hardware and this clearly indicates that they expect most of their drives to last at least this long
other estimates vary with arer suggesting that hard drives last 3 to 5 years whilst the Enterprise storage Forum reports that companies should plan for hard drives to last from 4 to 7 years some data storage organizations have also published research findings for example in March 2023 secure data recovery revealed an analysis of 27 failed hard drives here the average failed Drive had been powered for 2,233 hourss or just over 2 years 10 months in May 2023 cloud storage provider back Blaze reported a larger study of 17,1 155 failed drives where the average fail Drive had
been powered for 22360 hours or just over 2 years 6 months now whilst this is all excellent data it does not directly imply that most hard drives last for Less Than 3 years for a start whilst the age of a hard drive and it's powered on hours are likely to be very similar for drives operating in a data center this will not be the case in many consumer environments where PCS and laptops are not normally powered 24/7 and very importantly as both studies only looked at failed units longer lasting drives were less likely to have
been included in the experimental sample highlighting this point in 2021 back blaz had reported that 90% of its hard drives had been running for at least 4 years with 65% running for at least 6 years given that b Blaze operates over 200,000 consumer quality hard drives and its data centers this analysis suggests that if we buy a new hard drive it has a 2/3 chance of operating for at least 6 years however before we get too excited it's worth remembering that this data relates to hard drives running in a data center in ideal environmentally controlled
conditions in contrast drives in consumer PCS and in particular in laptops and external enclosures are likely to be subject to physical shocks vibrations power surg and temperature changes that may considerably reduce their lifespan and so my earlier assertion that most hard drives will last 3 to 7 years does remain a reasonable proposition but there is no doubt that some hard drives will run much longer and personally I own two 20-year-old Western Digital Raptors that are still working perfectly finally it's worth noting that hard drives are subject to data fade or bit Ro over time this
means that if you write data to a new drive and then store it for 20 years the data May no longer be readable even if a drive remains in perfect working order this is due to magnetic field Decay and can only be protected against by regularly refreshing data by rewriting it how often this needs to occur is a matter of debate but rewriting the contents of a hard drive every 5 years is probably wise and every 2 years for critical archive or backup files next let's reflect on the life expectancy of other magnetic media still
today data cartridges containing a spool of tape remain popular for backups or archiving purposes as noted earlier when stored in optimal conditions these May retain information for up to 30 years and whilst this older version 3 linear open tape cartridge Only Stores 400 GB of uncompressed data the latest L9 cartridges in the same form factor offer 18 terab of non-compressed storage for around $100 over the years many other removable magnetic media have been used for data storage including floppy diss zip and Jazz cartridges and even sycl micro drives these may all in Theory have a
life expectancy of 5 to 10 years and possibly far more but for most users their lifespan has now being constrained by the lack of availability of Hardware able to read them solid state drives or ssds store data in flash memory cells on flash memory chips the memory cells are usually naned logic gates with two Technologies commonly employed named floating gate and charged trap flash to write or program data a voltage is applied to move electrons into the floating gate or charge trap this changes the resistance between the memory cell source and drain which can be
measured by passing a current between them whilst Nan flash cells can be individually written they can only be erased in blocks to do this a voltage is applied to remove the electrons from the flo flating gate or charged trap however repeated program arrays operations weaken the materials the cells are made from which result in electrons either escaping a floating gate or being retained in the charged trap and after a certain number of program arrays or PE Cycles it therefore becomes impossible for the cells to reliably function the number of PE cycles of flash memory cell
can sustain in part depends on how much data it has to hold initially all ssds stored just one bit of data per cell which we now refer to as single level cell or SLC however to scale up capacities for a reasonable cost multi-level cell or mlc ssds were developed followed by triple level cell or TLC and quad level cell or qlc these store more bits per memory cell by distinguishing additional States between fully programmed and fully erased however as the cell Weare out an electron stray it's more difficult to distinguish these extra states which means
that the cells can endure fewer PE Cycles the average number of PE Cycles is different for Consumer and Enterprise hardware and also varies between models and manufacturers but as a guide today SLC drives can sustain about 100,000 PE Cycles mlc between about 3,000 and 10,000 TLC between 500 and 3,000 and qlc between 300 and 1,000 and today manufacturer guarantees tend to reflect the lower end of this range for example Samsung's 1 tbte 990 Evo and 990 Pro ssds have a warranty of 600 terab written which equates to 600 PE cycles for these TLC drives and
it's no surprise that the 2 terb models based on the same flash memory cells have 12200 100 terabyt written warranties this also highlights how if you want an SSD that can endure a lot of right activity it's wise to choose one with the highest capacity you can afford today almost all and user ssds are TLC or qlc and I know this worries many people but even a 600 terab written warranty for Samsung's 1 tbte TLC ssds equates to 100 GB written every day for 6,000 days or 16.4 years and today most manufacturers do claim that
their ssds should last 10 years or more in normal use however I've never seen a warranty greater than 5 years and so stating the average life expectancy of an SSD to be between 5 and 10 years in normal use is a reasonable if potentially conservative proposition this point noted ssds can suffer from Daya fade as over time electrons May leak from their floating Gates or charge traps this is more likely to occur at high or low temperatures and if the memory cells have endured a high proportion of their viable PE Cycles to mitigate this problem
modern SSD controllers use a read scrub technology that scans the drive during idle periods and rewrites the data in any flash memory block that has fallen below a safe retention threshold in theory this means that a regularly powered SSD ought to be able to retain data for the full life of the drive unfortunately when an SSD is not powered it cannot execute refresh operations and this will limit how long data is retained in 2010 The Joint electron device engineering Council or jedc set an SSD standard that requires client ssds to retain data for 365 days
when powered off and stored at 30° today new ssds from compliant manufacturers will probably retain data for two or more years when powered off and stored at a moderate temperature however if you intend to use ssds as archived media do not use drives that have endured most of their PE Cycles do not store above 30° and ideally leave the drive powered for several hours on at least an annual basis memory cards and USB thumb drives are based on the same Solid State Technology as ssds and therefore ought to exhibit the same life expectancy characteristics and
indeed the SD card Association claimed that the lifespan of an SD card is now 10 years or more in normal use however to protect data always safely eject USB flash drives and memory cards before removing them and as with ssds there is no guarantee that a non-powered USB drive or memory card will retain data for any length of time and personally I wouldn't trust one to keep data safe for more than a year writable Optical media record data by using a laser to change the properties of a layer of dye many different kinds of dyes
and other material can be used to make writable and rewritable CDs DVDs and Blu-ray discs and all of these produced media with different data retention characteristics it's not uncommon for the data on some writable Optical media to fade after only a few years however if highquality branded media are used data is recorded at a moderate speed and the discs are stored in a cool dry environment Optical discs can make excellent archive media and for me personally this generally means using verbatims gold archival media written at the lowest speed my software and drive support whilst researching
this video I came across this fantastic paper from the Canadian conservation Institute this explains the data retention characteristics of discs made from all possible materials and concludes with this excellent table that charts their average life expectancy in summary this tells us that the highest quality writable CDs should retain data for at least 20 years with gold disc expected to last 100 years or more gold dvdr should then last at least 50 years and gold bdr at least 10 years in General rewritable Media have a shorter life expectancy as do high capacity multi-layer discs longtime viewers
of this channel may recall that in 2016 I made a video on mdisk which is a form of dvdr and bdr media that uses inorganic rather than organic dyes in theory this allows mdisks to retain data for 1,000 years although tests of this are inevitably based on accelerated aging note that data has to be written to M disks using a special burner although they can be read in most Standard Optical drives usually when I mention Optical media there are comments that nobody uses them anymore and that Hardware is no longer available however quality internal and
external drives do remain on the market such as the external Pioneer bdr x13 which was launched in 2022 this is absolutely not a product for the average consumer but it's far cheaper than a tape drive and allows the creation of long-term archival media as the ancient Egyptians proved the second best way to immortalize data is to carve it into stone however the very best way to ensure that your information is never lost is to encode it into a self-replicating media such as living DNA unfortunately right now Stone and DNA are not available a general means
of digital data storage however we can all copy DNA's trick of constantly replicating data to maintain it and I hope that in that context this video has given you useful information on when different types of storage media need to be duplicated but now that's it for another video if you've enjoyed what you've seen here please press that like button if you haven't subscribed Please Subscribe and I hope to talk to you again very [Music] soon
