On Tuesday, August 21, 2018 at 6:21:22 PM UTC+2, Marcus Linsner wrote: > > > One of the Samsung SSD 850 PRO disk achieved a figure of 9.1 Petabyte of > > > data > > > written! That´s 60 times the TBW figure Samsung promises on its data > > > sheets. > > > The cheaper Samsung product – Samsung SSD 750 Evo was able to write 1.2 > > > Petabyte of data, which equals in theory to more than 80 years of constant > > > disk writing. However, the pro models showed why their price is higher: > > > None > > > of them wrote less than 2.2 Petabyte of data.
Actually I have to correct the record here. Basically I was wrong about the cause of this 2MB/sec write speed being caused by that new Samsung firmware update: > I'm not trusting Samsung when it comes to SSDs anymore, ever since they > botched the firmware for 840 EVO where it periodically(actually at least once > per day!) rewrites everything in order to improve read speeds(except when > this rewriting takes place and lasts for hours, during which the random read > speed for 1 thread 4K is no bigger than 2 megs per sec), no doubt at the cost > of disk life and yet without updating the S.M.A.R.T. LBAs written counter: > https://www.anandtech.com/show/9196/samsung-releases-second-840-evo-fix > There used to be a system-wise OS freeze whenever the SSD just passed another > 1TB of bytes written which took like 1-2 minutes, and those are now happening > at least once a week. The bad thing is that you can't roll back to any > previous firmware version and there's no way to stop this automatic rewriting > from happening. The fact is, I don't know when that rewriting/refreshing takes place(it could be even more often than I thought, if judging by the SSD temperature being usually 44-47 Celsius, and only sometimes 32-35 Celsius)! What I was seeing as 2MB/sec was in fact a quirk of my Lenovo Ideapad Z575 laptop whereby after one(and any subsequent) Windows 7 Restart (ie. Start->Restart) the random write speed would be capped(I don't know why) to that 2MB/sec and only a Sleep or Shutdown would bring it back to normal! And this only happens when the SSD is connected via a drive caddy in place of the optical disk drive(ODD), alone with nothing else connected (on ESATA, or main drive bay). But how do I know it's not the SSD still? Because I added a Kingston SSD on the ESATA port, in addition to the Samsung SSD which sits in the ODD bay, and the speeds for both are normal until after the first reboot from Linux after which the Kingston's random write speed is at around 2 MB/sec, whilst the Samsung's is just normal. Proof of that here: https://gist.github.com/constantoverride/7fc7974eb0d5dd48f4ebe5bc84e623f3#gistcomment-2713671 So that's why I deduced that it cannot be Samsung SSD's fault for this write speed decrease. The disk life being decreased due to refreshing is just my guess based on my assumption(possibly wrong?) that there's no way to refresh without decreasing cell lifespan. The other one with 1-2minutes of freeze is still true, it was happening even when Samsung SSD was on main drive bay alone(they were just rarer) -- You received this message because you are subscribed to the Google Groups "qubes-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/qubes-devel/b20645e1-b311-4ef9-85c4-93318724700b%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
