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How much is one terabyte of data?

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Re: How much is one terabyte of data?

#4
post #3

> The high-speed SSD reads 300 megabytes of data per second Aren't normal SSDs now at 500-600MB/s read? And then there are nvme SSDs which can read up to 7GB/s

I'm pretty sure they mean HDDs as they write hard disks in each paragraph below.

I don't think there are HDDs that can read 300MB/s

Re: How much is one terabyte of data?

#5
post #3

Earlier quoted context omitted.

I'm pretty sure they mean HDDs as they write hard disks in each paragraph below.

I don't think there are HDDs that can read 300MB/s

https://www.seagate.com/content/dam/seagate/migrated-assets/...

Claims 500 MB/s. But of course your chances of getting that from a hard disk are far less than from a SSD.

Re: How much is one terabyte of data?

#6
post #3

Earlier quoted context omitted.

I'm pretty sure they mean HDDs as they write hard disks in each paragraph below.

I don't think there are HDDs that can read 300MB/s

I mostly play with 7200RPM consumer drives, they hang around there in ideal situations: sequential non-fragmented reads

Not to put stock in the assertion, I have no idea what the article intends

Re: How much is one terabyte of data?

#7
1 million is 100^3 (i.e. a cube 1 metre across, contains a million 1 cm cubes)

1 billion is 1000^3 (1 m cube contains a billion 1 mm cubes)

1 trillion is 10,000^3 (I can't visualize 0.1 mm, so increase size: the big cube is now 10 m on side, with 1 mm parts)

So the million and billion you could have on your desk made of parts that you can see and handle; the trillion is just a bit too big for that, you'd need a big room with a high ceiling.

Edit: and, of course, you can also see a million in 2D. A sheet of grid paper 1 m across, with 1mm grid squares. Or, more practically, try counting the pixels on a 720p monitor: 921600 pixels on that screen. Use checkerboard pattern.

Re: How much is one terabyte of data?

#8

> The high-speed SSD reads 300 megabytes of data per second Aren't normal SSDs now at 500-600MB/s read? And then there are nvme SSDs which can read up to 7GB/s

This tripped me up as well. While modern NAND SSDs do slow down to about a third of the advertised speeds on non-sequential reads/writes, that is still 2-3 GB/s. The "normal" (SATA) SSDs are just limited by SATA's link speed, they could easily get to similar rates.

Re: How much is one terabyte of data?

#9

> The high-speed SSD reads 300 megabytes of data per second Aren't normal SSDs now at 500-600MB/s read? And then there are nvme SSDs which can read up to 7GB/s

"Up to xyz MB/s"

This very detail is the reason USB flash drives have useless performance numbers on them, which oftentimes lead to 1/100th of the advertised performance.

Everything that's bigger than the sector size (4k) is usually far lower than those numbers.

Re: How much is one terabyte of data?

#10

1 million is 100^3 (i.e. a cube 1 metre across, contains a million 1 cm cubes) 1 billion is 1000^3 (1 m cube contains a billion 1 mm cubes) 1 trillion is 10,000^3 (I can't visualize 0.1 mm, so increase size: the big cube is now 10 m on side, with 1 mm parts) So the million and billion you could have on your desk made of parts that you can see and handle; the trillion is just a bit too big for that, you'd need a big r…

There are ink pens with 0.1 mm tips. https://www.jetpens.com/Copic-Multiliner-SP-Pen-0.1-mm-Black...
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