Creating chia plots using ram ONLY? No endurance issues?

[babadoctor]

If I use a ram to create a plot, shouldn't I theoretically not have to worry about disk endurance? Or is the process of having the plot on a hard disk write intensive as well?

 

I found some videos about it, but I couldn't find anything specific about it.

 

I am thinking that it may be possible to mine chia on /dev/shm on linux, or something but I can't find any tutorials.

 

Shouldn't mining chia on ram not have any of the endurance issues people are facing with buying traditional ssds?

 

What is the best way to go about this?

 

[NunoLava1998]

Problem is, it would be very very expensive, as each Chia plot is 101GiB large. 1TB of DDR3 RAM on eBay is about 2,000$, so you'd spend at the very minimum just under 200$ per plot.

[mariushm]

You could create a RAM drive which shows up in the operating system like a regular hard drive, so Chia wouldn't have any clue about it. 

 

But think about it ... from what I heard, it uses around 200-250 GB of disk space plus some temporary files during mining of one plot ... so at most you'd probably be able to mine 2 plots at same time using 512 GB of memory... so you'd have an expensive system with lots of threads that can only use 2-3 threads for mining 

DDR4 is also expensive, so you'd be paying a lot for ddr4 registered / buffered memory to get to your 512 GB / 1 TB of ram.

 

I was thinking about it, using G34 (old AMD opteron motherboards)... you could have bought a dual socket g34 motherboard WITH 2 opteron processors for around 100-150$ .. and then fill it with cheaper DDR3 server sticks. 

BUT, those opteron processors are really slow, so on one hand you are saving money by not killing your ssd drives but you're paying more in electricity for powering two opterons and all the ram sticks and because the ipc sucks (low performance per core)  it would take way more time for a plot to be mined, so you wouldn't be efficient. 

 

[BondiBlue]

Yes, making a RAM drive would work fine, but if you don't have the RAM and a system to go with it already then I wouldn't put that kind of money into it. You'll need somewhere around 300GB per plot for temp storage, and that's a lot of RAM. If you're using an older platform with loads of DDR3 you'll be hurting your efficiency both in terms of power and plotting performance (if you go too old, that is), and if you're using something newer the price would be absurd unless you've already got the hardware. Plus, you'll also need somewhere to store all of this stuff, and if you're looking into using RAM for plotting then you'll probably need a large farm. 

[babadoctor]

5 minutes ago, NunoLava1998 said:

Problem is, it would be very very expensive, as each Chia plot is 101GiB large. 1TB of DDR3 RAM on eBay is about 2,000$, so you'd spend at the very minimum just under 200$ per plot.

Why does it need to be 1TB of ram? Can't I just have 256gb of ram and move the plot over to a mechanical drive after it's done generating the plot?

or would it be too slow?

 

7 minutes ago, mariushm said:

You could create a RAM drive which shows up in the operating system like a regular hard drive, so Chia wouldn't have any clue about it. 

 

But think about it ... from what I heard, it uses around 200-250 GB of disk space plus some temporary files during mining of one plot ... so at most you'd probably be able to mine 2 plots at same time using 512 GB of memory... so you'd have an expensive system with lots of threads that can only use 2-3 threads for mining 

DDR4 is also expensive, so you'd be paying a lot for ddr4 registered / buffered memory to get to your 512 GB / 1 TB of ram.

 

I was thinking about it, using G34 (old AMD opteron motherboards)... you could have bought a dual socket g34 motherboard WITH 2 opteron processors for around 100-150$ .. and then fill it with cheaper DDR3 server sticks. 

BUT, those opteron processors are really slow, so on one hand you are saving money by not killing your ssd drives but you're paying more in electricity for powering two opterons and all the ram sticks and because the ipc sucks (low performance per core)  it would take way more time for a plot to be mined, so you wouldn't be efficient. 

 

Interesting

 

So the power usage for powering the ram sticks / CPU is a lot more cost intensive than just powering an ssd?

 

I thought the cpu would be doing the operations anyways since it needed to generate the plot anyways

 

[NunoLava1998]

2 minutes ago, babadoctor said:

Why does it need to be 1TB of ram? Can't I just have 256gb of ram and move the plot over to a mechanical drive after it's done generating the plot?

or would it be too slow?

I guess, I just did 1TB as looking on eBay it's cheaper per gigabyte than buying 128/256gb

[BondiBlue]

3 minutes ago, babadoctor said:

Why does it need to be 1TB of ram? Can't I just have 256gb of ram and move the plot over to a mechanical drive after it's done generating the plot?

or would it be too slow?

Honestly, if you're only going to use 256GB of RAM for plotting (and that's kind of iffy from my experience - 256GB seems to be just a bit too small for one plot) then you'd be much better off just buying a ton of SSDs for the same money. I only see RAM being a good option on a very large scale, not just for one plot. 

[babadoctor]

1 minute ago, BondiBlue said:

Honestly, if you're only going to use 256GB of RAM for plotting (and that's kind of iffy from my experience - 256GB seems to be just a bit too small for one plot) then you'd be much better off just buying a ton of SSDs for the same money. 

I would be interested in seeing a chart of the initial cost vs the potential savings over time as the cost of SSDs and other storage mediums increase.

You're probably right though, it may only benefit in the long run.

[Kilrah]

Apart from phase 1 plotting is a single thread process, so doing only 1 plot at a time is terribly inefficient. If you "only" have enough RAM to make 1 simuntaneous plot you basically won't gain anything vs it being on an SSD, and on an SSD you can make 8 in parallel. Of course there's no wear with the RAM, but it'd cost you more in "not being fast enough" than what SSDs cost.

[BondiBlue]

Just now, babadoctor said:

I would be interested in seeing a chart of the initial cost vs the potential savings over time as the cost of SSDs and other storage mediums increase.

You're probably right though, it may only benefit in the long run.

RAM isn't really something I'd personally consider. I can easily do 4 plots at a time between 2 SSDs in my machine, and that's only because I run out of RAM for my system to function. If I had a bit more RAM or set lower limits I could do a couple more at a time. I don't see how using a RAM disk would be much better for that. And besides, if I kill both of the SSDs I was using (I've stopped plotting) they cost me less than $200 combined, so no big deal. 

[babadoctor]

Just now, Kilrah said:

Apart from phase 1 plotting is a single thread process, so doing only 1 plot at a time is terribly inefficient. If you "only" have enough RAM to make 1 simuntaneous plot you basically won't gain anything vs it being on an SSD, and on an SSD you can make 8 in parallel. 

I did not know that you could make 8 in parallel on an SSD. Well, that definitely puts an end to that idea.

[mariushm]

9 minutes ago, babadoctor said:

Why does it need to be 1TB of ram? Can't I just have 256gb of ram and move the plot over to a mechanical drive after it's done generating the plot?

or would it be too slow?

 

Interesting

 

So the power usage for powering the ram sticks / CPU is a lot more cost intensive than just powering an ssd?

 

I thought the cpu would be doing the operations anyways since it needed to generate the plot anyways

 

Well, look at it this way... 

The final plot on your disk is around 100 GB, but while that plot is processed I heard it may take up to 200-250 GB of disk space.  So you need to reserve that 250 GB or whatever it's needed for each plot. 

There's a significant amount of CPU power used to calculate the data written in the plots and if you want to make a profit / be competitive, you want to mine multiple plots in parallel to keep the cpu busy. It would not be efficient and cheap to have a $500-1000 cpu with 16+ cores and only use 2 cores to mine one or two plots at a time

 

Each regular desktop ram stick uses maybe 2 watts. A server stick may use 3-5 watts, especially if it's the "buffered" kind. If you have let's say 16 sticks of DDR3 on a dual socket motherboard, you're looking at 16 x 3-4w = around 50 watts just for the ram sticks. Then, you also have the power used by two memory controllers inside the CPUs, which have to deal 4 channels and 2 sticks per channel, so they use more power compared to regular desktop processors that have just 2 channels. 

You'll also have to cool the ram sticks with one or two fans because so many sticks packed together producing that much heat need to be cooled - in servers they ram slots are positioned in such a way that the high power fans in front of the case push air over them and keep them cool - if you don't have a case like that, you need to add fans, and that's another 5-10w 

 

So let's say 75w just for ram sticks + fans  ... compare that to around 10w power consumption of a nvme SSD. 

 

The processors are also old and fairly inefficient, so let's say you'd be consuming maybe 40-60w per CPU mining just two plots... 

 

 

Watch derbauer's video about mining chia on Youtube ... he explains how he mined around 6 plots in parallel with a very powerful machine...