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Google said 50% better price/performance, and I believe Google's culture is less tolerant of marketing "exaggerations" than is Amazon's. As a simple, concrete,

Google said 50% better price/performance, and I believe Google's culture is less tolerant of marketing "exaggerations" than is Amazon's. As a simple, concrete, example: Amazon's GBs are 10^9 bytes; Google and the rest of the world defines them as 2^30. That's why EC2 instances have such weird memory sizes. So EC2's "17.1 GB" is what the rest of the world calls 16GB.

saurik 14y ago
No: hard drive manufactures and in fact most storage uses define gigabytes the way Amazon does. If you want to talk about gibibytes, please use tr appropriate terminology.
- justinsb 14y ago
  Well, I think that's still controversial, but it sells hard drives. For RAM, I still buy a 16GB DIMM; if I buy it from Amazon I expect it to show up as 16GB, not 14.9GB. With EC2, that's not the case. But the point is that I trust Google, when I see something from Amazon I know to check the fine print.
wmf 14y ago
I'm pretty sure that is not the case. I couldn't find data for xlarge, but here's a dmesg snippet from a small instance: Memory: 1711020k/1748992k available (2071k kernel code, 28636k reserved, 1080k data, 188k init, 1003528k highmem) That's pretty close to 1.7 GiB. Here's a large instance: Memory: 7635512k/7864320k available (3204k kernel code, 388k absent, 228420k reserved, 3714k data, 500k init) That looks like 7.5 GiB to me, just as Amazon claims. 17.1 GiB is actually quite normal when you consider than Nehalems have 3 memory channels with 3 DIMMs/channel so you get numbers like 18, 36, 72, or 144 and then subtract some Xen overhead.
- justinsb 14y ago
  Interesting - and your 9 DIMM argument makes sense. The large is exactly 7.5 * 2^30. The small is about 1.66 on the same scale, which isn't outrageous to round to 1.7. I guess I'll check the state of play on e.g. the 68.4 GB machine, which is where it would really make a difference!
oh_sigh 14y ago
Laughable. A GB is defined as 10^9 bytes. 2^30 bytes is a GiB, or Gibibyte. Just because you don't use appropriate terminology doesn't mean that Amazon exaggerates.

saurik 14y ago

No: hard drive manufactures and in fact most storage uses define gigabytes the way Amazon does. If you want to talk about gibibytes, please use tr appropriate terminology.

justinsb 14y ago
Well, I think that's still controversial, but it sells hard drives. For RAM, I still buy a 16GB DIMM; if I buy it from Amazon I expect it to show up as 16GB, not 14.9GB. With EC2, that's not the case. But the point is that I trust Google, when I see something from Amazon I know to check the fine print.

wmf 14y ago

I'm pretty sure that is not the case. I couldn't find data for xlarge, but here's a dmesg snippet from a small instance: Memory: 1711020k/1748992k available (2071k kernel code, 28636k reserved, 1080k data, 188k init, 1003528k highmem) That's pretty close to 1.7 GiB. Here's a large instance: Memory: 7635512k/7864320k available (3204k kernel code, 388k absent, 228420k reserved, 3714k data, 500k init) That looks like 7.5 GiB to me, just as Amazon claims. 17.1 GiB is actually quite normal when you consider than Nehalems have 3 memory channels with 3 DIMMs/channel so you get numbers like 18, 36, 72, or 144 and then subtract some Xen overhead.

justinsb 14y ago
Interesting - and your 9 DIMM argument makes sense. The large is exactly 7.5 * 2^30. The small is about 1.66 on the same scale, which isn't outrageous to round to 1.7. I guess I'll check the state of play on e.g. the 68.4 GB machine, which is where it would really make a difference!

oh_sigh 14y ago

Laughable. A GB is defined as 10^9 bytes. 2^30 bytes is a GiB, or Gibibyte. Just because you don't use appropriate terminology doesn't mean that Amazon exaggerates.