Samsung SSD PM1643 3.8TB SAS 12Gb/s MZ-ILT3T8A 2.5" @ $289.98

Firebug24k

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Apr 12, 2017
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Eh, even with overhead you're looking at more like 1200MB/sec. And there's nothing you can do to make it faster, that's the downside of SAS vs NVME

Edit: I'm wrong, I didn't think about dual port, you can do that w/appropriate hardware & software support as said below. You won't improve write speed much but looks like you might gain some on read.
 
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Rand__

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Mar 6, 2014
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These are rated for 2000 MB/s but 12 Gbps is gonna limit that to 1000 right? How could you connect these in a way that would unlock the full speed of the drive?
sas multipath? (ie sas dual expander backplane + 2 HBAs + OS multipath IO support)
 

itronin

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Nov 24, 2018
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These are rated for 2000 MB/s but 12 Gbps is gonna limit that to 1000 right? How could you connect these in a way that would unlock the full speed of the drive?
dual port and storage software that would take advantage of it.

Edit @Rand__ with the more detailed explanation. sorry didn't see your response.
 

nev_neo

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Jul 31, 2013
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Mine came in with 520bit sector size. I tried using sg_utils in ubuntu 18.04 but couldnt get it to work. Ended up loading freenas and doing a camcontrol format. They are now loaded in my vSAN cluster - going to use them as storage drives.

Edit: Commands used were -
# camcontrol cmd daxx -v -c "15 10 0 0 v:i1 0" 12 -o 12 "0 0 0 8 0 0:i3 0 v:i3" 512
# camcontrol format daxx -y
Didnt take too long to format, probably less than 10minutes each.
 
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TheServerGuy

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Dec 18, 2016
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These drives are beautiful. If anyone bought too many from this deal, I'd definitely grab them for $350.
 

Churchill

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Jan 6, 2016
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Yeah closer to $500 was our best price we could see for a large amount this was for 50 drives.
We got our last big order of them for $298 :(
Stupid chia mining has ripped the market up. Guess time to join them?
itll be just like the bitcoin rush for GPUs and then all these ssds will flood the market used for pennies on the dollar.
 

wifiholic

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Mar 27, 2018
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itll be just like the bitcoin rush for GPUs and then all these ssds will flood the market used for pennies on the dollar.
If I ever buy another SSD on eBay, I'm going to want to see proof of remaining usable life. Plotting Chia on an SSD 24/7 is going to run it into the ground.
 

Weapon

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Oct 19, 2013
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If I ever buy another SSD on eBay, I'm going to want to see proof of remaining usable life. Plotting Chia on an SSD 24/7 is going to run it into the ground.
Maybe on a consumer TLC drive. These drives are good for like 7 PB. Would take a lot of chia to eat that up.
 

funkywizard

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Jan 15, 2017
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If I ever buy another SSD on eBay, I'm going to want to see proof of remaining usable life. Plotting Chia on an SSD 24/7 is going to run it into the ground.
Yeah it depends on the drive. Any NVMe with less than 1 drive write per day endurance rating will be dicey.

From here forward I would avoid buying used drives with a 0.3 DWPD rating, which is fairly typical for "read intensive" SSDs. Anything with a 3 DWPD rating or higher will probably be fine. And drives with 1 DWPD endurance could go either way.

Sata SSDs, being slow and therefore not terribly useful for Chia, should be somewhat safer, although the similar rules apply in my mind -- 0.3 DWPD drives will be risky, 1 DWPD drives will probably be fine, and 3 DWPD and higher will almost certainly be ok.

SAS is kind of in between in speeds and so the amount of abuse they could possibly receive is also halfway between.

A high end plotter with 3x fast 3.84tb nvme I've been able to plot 6 - 7tb / day, which requires maybe 100tb / day of writes split across 3 drives, so call it 35tb / day writes per drive -- 9 drive writes per day. These are 1 DWPD x 5 years drives, so at this level of abuse they're rated for maybe 7 months of endurance. I'll only be plotting for a month on these give or take so they'll be just fine.

If the gold rush continues for several more months, then you'll want to have a skeptical eye towards 1 DWPD drives. If it ended tomorrow, those would be fine almost for sure. And a 3 DWPD drive could probably handle this abuse for a year and still have 50% wear remaining.
 
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EasyRhino

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Aug 6, 2019
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The GPU crash was around 2018, you've missed it :) Hopefully there will be another one.

If the gold rush continues for several more months, then you'll want to have a skeptical eye towards 1 DWPD drives. If it ended tomorrow, those would be fine almost for sure. And a 3 DWPD drive could probably handle this abuse for a year and still have 50% wear remaining.
I agree it's pretty strange that we're going to start needing proof-of-life-left for SSDs. This is actually worse than wiped SMART info on a HDD because too much wear will eventually always grind a SSD into dust.

Although a "mostly depleted" SSD might be good for something like a scratch drive or more chia plotting.

I'm actually plotting chia on a HDD with over 2000 bad sectors and it's actually a few hours slower than than an identical HDD that's not failing.