On 29.12.2019 15:49, shirish शिरीष wrote: > Hi all, > > I read Alexander's reply with interest at [1] . > > @Alexander, thank you for taking time to answer my question/s . Maybe > you can CC me the next time :) > > What was also interesting in your answer was the use of dark marketing > practises used by some manufacturers to disguise TLC (3-bit NAND) > memory chips as MLC ones but haven't shared either literature or any > tools to tell them apart. > Worst offender of this trickery is Samsung. You have to carefully read through full specifications for each device that available on official web sites, which are often hidden behind very long page scrolls and many clicks. Basically, if it says "4-bit" it means drive was build with QLC NAND type. And if it says "3-bit" it means TLC NAND type. And if it says "2-bit" it means MLC NAND type. And if some information is not available on official web site of some manufacturer, personally I'd search for another SSD elsewhere. There are also utilities that can view exact specifications of SSD, but I don't know if similar programs exist for Linux. [1] These kinds of utilities rely on internal database of known devices (nand chips, controllers, SSDs), so they can't simply identify any and all SSDs as is. If you have identified exact NAND chip and its manufacturer you can look up specifications for chips alone to see their, for an example, write endurance, which varies and could be different for each NAND type. [2]
> You shared something called TBW or DWPD ratings for SSD but again > didn't share anything about that. Any links or literature which will > help me find a bit more about them and perhaps what you have used it > for ? My workload varies, sometimes it is compiling, sometimes it is > running some tests, sometimes doing gaming and sometimes just browsing > and using multimedia (movies etc.) . So my idea and stress would be > general system improvements and response times. Also my budget is not > that great, at the most I could afford is either a 500 GB to 1 TB There is a good article to read about this. [3] > > I have also been reading about multi-actuator heads [2] in traditional > HDD's but guessing they will be probably be priced and used by > enterprise more rather than the enthusiast class at least in the > beginning. I also have read blackbaze hdd failures to get some ideas > about what's good or not even though their use-case scenario is far > bigger than mine.[3] > > For e.g. for me the question would be how to deal with backups and > crashes if a time comes, as checking 4 TB hdd's is also insane, at > least in my puny setup. > > Looking forward to know more. > > 1. https://lists.debian.org/debian-user/2019/12/msg00726.html > 2. > https://blog.seagate.com/craftsman-ship/multi-actuator-technology-a-new-performance-breakthrough/ > 3. https://www.backblaze.com/blog/hard-drive-reliability-stats-q1-2016/ > Personally, I use self-hosted NAS with RAID1 build from 2x 4TB NAS grade HDDs. Because I like to keep my data private and I like the idea of giving up storage space of one HDD drive as insurance for data safety. >From my personal experience over many years, I can see how HDDs could fail in many different ways, long before SMART will mark them as "Failed". But it is very unlikely (and unfortunate) to buy a brand new HDD that will fail during it's warranty period, and if it worked fine before chances are high it will continue to work for many years after warranty period expires. Fun fact: I still have my ~20 years old 3.5" Fujitsu 20GB IDE HDD that is still alive and kicking. :) [1] http://aezay.dk/aezay/ssdz/ [2] https://en.wikipedia.org/wiki/Flash_memory#Write_endurance [3] https://techcommunity.microsoft.com/t5/Storage-at-Microsoft/Understanding-SSD-endurance-drive-writes-per-day-DWPD-terabytes/ba-p/426024 -- With kindest regards, Alexander. ⢀⣴⠾⠻⢶⣦⠀ ⣾⠁⢠⠒⠀⣿⡁ Debian - The universal operating system ⢿⡄⠘⠷⠚⠋⠀ https://www.debian.org ⠈⠳⣄⠀⠀⠀⠀
