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Does my data fit in RAM?

yourdatafitsinram.net

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Re: Does my data fit in RAM?

#51
post #43

The problem is DRAM price hasn't drop one bit. The lowest price floor per GB has been similar for the past decade. Roughly at $2.8/GB in 2012, 2016, and 2019. And all DRAM manufacturers has been enjoying a very profitable period. And yet our Data size continue to grow. We can fit more Data inside memory not because DRAM capacity has increase, but we are simply increasing memory channels.

just wait for China to enter the mkt in thia decade...

Re: Does my data fit in RAM?

#52
post #29

While pithy, the implication that you are going to process 12 TB of data in RAM using mostly single-threaded tools doesn't reflect reality.

Where exactly does that implication come from? Are you from a world where you need a map reduce framework + cluster to have parallelism of any kind?

No, but I frequently see people implying that you can do your data science in Python and R as long as you can fit the data in RAM. As you mention, it's not RAM that's the limiting factor for larger data volumes, it's finding tools that exploit parallelism.

Re: Does my data fit in RAM?

#53
post #29

Earlier quoted context omitted.

Where exactly does that implication come from? Are you from a world where you need a map reduce framework + cluster to have parallelism of any kind?

No, but I frequently see people implying that you can do your data science in Python and R as long as you can fit the data in RAM. As you mention, it's not RAM that's the limiting factor for larger data volumes, it's finding tools that exploit parallelism.

I have done plenty of parallel work in python and R, so I'm still not sure what you mean.

Re: Does my data fit in RAM?

#56

$2,000 each for 128GB LRDIMMs, 48 of those will be $100,000 and then you'll need another $20,000 to buy the rest of the server it goes in.

if you can get by with 4TB, it's less than $30/hr on AWS

What is? Anything I touch on AWS is 5k a month. /s

Re: Does my data fit in RAM?

#57
post #43

The problem is DRAM price hasn't drop one bit. The lowest price floor per GB has been similar for the past decade. Roughly at $2.8/GB in 2012, 2016, and 2019. And all DRAM manufacturers has been enjoying a very profitable period. And yet our Data size continue to grow. We can fit more Data inside memory not because DRAM capacity has increase, but we are simply increasing memory channels.

Everyone knows that DRAM prices have been in a collapse since early this year, but last week DRAM prices hit a historic low point on the spot market. Based on data the Memory Guy collected from spot-price source InSpectrum, the lowest spot price per gigabyte for branded DRAM reached $2.59 last week.

https://thememoryguy.com/dram-prices-hit-historic-low/

You've selected out the low points on the graph: 2012, 2016, and 2019, most of the time DRAM has not been available at these prices. Now is definitely the time to load up on RAM.

Re: Does my data fit in RAM?

#58
post #30
post #2

Legit question: I have a dataset that's a terabyte in size spread over multiple tables, but my queries often involve complex self joins and filters; for various reasons, I'd prefer to be able to write my queries in SQL (or spark code) because it's the most expressive system I've seen. What tool should I use it to load this dataset on RAM and run these queries?

You can get a box with 4TB of ram on EC2 for $4/hr spot, so copy your data into /dev/shm and go hog wild. For lots of databases, most of their time is spent locking and copying data around, so depending on your workload you might getsignificant speedups in Pandas/Numpy if it's just you doing manipulations, and there are multicore just-in-time compilers for lots of Pandas/Numpy operations (like Numba/Dask/etc). If you…

How long does it take to copy your data in? And what’s the bandwidth cost involved?

People like to talk about the elasticity or compute, but startup is not free (or even cheap in most cases).

Re: Does my data fit in RAM?

#59
post #43

The problem is DRAM price hasn't drop one bit. The lowest price floor per GB has been similar for the past decade. Roughly at $2.8/GB in 2012, 2016, and 2019. And all DRAM manufacturers has been enjoying a very profitable period. And yet our Data size continue to grow. We can fit more Data inside memory not because DRAM capacity has increase, but we are simply increasing memory channels.

[deleted]

Re: Does my data fit in RAM?

#60
post #41
post #36

Earlier quoted context omitted.

If the result is faster than a $250K Hadoop cluster then you're still ahead.

the way things today, the Hadoop cluster will be just a bit faster on that thing. 25 years ago i was suggesting clients to upgrade from 4MB to 6-8MB as it was improving their experience with our business software, these days i've already suggested a couple of customers to upgrade from 6TB and 8TB respectively ... as it would improve their experience with our business software. What's funny is that customer experience…

Everything is way too much bloat now
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