RAM
Characteristics
| Name | Unit | Default value | Description | Example |
|---|---|---|---|---|
| units | None | 1 | RAM strip quantity | 2 |
| usage | None | See Usage | See usage | .. |
| capacity | GB | 32 | Capacity of a ram strip | 12 |
| density | GB/cm2 | 0.625 | Size of the die per Go of a ram strip | 1.25 |
| process | nm | None | Engraving process (Architecture) | 25 |
| manufacturer | None | None | Name of the ram manufacturer | Samsung |
| model | None | None | .. | .. |
Complete
The following variables can be completed
density
if process or/and manufacturer are given, density can be retrieved from a fuzzy matching on our ram repository.
If several ram matches the given process or/and manufacturer the maximizing value is given (in terms of impacts).
Manufacture impact
For one RAM bank the manufacture impact is:
with:
| Constant | Units | Value |
|---|---|---|
| \(\text{RAM}_\text{manufacture_die}^\text{gwp}\) | kgCO2eq/cm2 | 2.20 |
| \(\text{RAM}_\text{manufacture_die}^\text{adp}\) | kgSbeq/cm2 | 6.30E-05 |
| \(\text{RAM}_\text{manufacture_die}^\text{pe}\) | MJ/cm2 | 27.30 |
| \(\text{RAM}_\text{manufacture_base}^\text{gwp}\) | kgCO2eq | 5.22 |
| \(\text{RAM}_\text{manufacture_base}^\text{adp}\) | kgSbeq | 1.69E-03 |
| \(\text{RAM}_\text{manufacture_base}^\text{pe}\) | MJ | 74.00 |
Note: If there are more than 1 RAM bank we multiply \(\text{RAM}_\text{manufacture}^\text{criteria}\) by the number of RAM bank given in units.
Usage impact
Both power consumption and consumption profile are implemented.
Consumption profile
The RAM consumption profile is of the form : consumption_profile(workload) = a * capacity
As a first approximation, we use a uniform consumption profile since the stress test data used show a rather uniform consumption. Consequently, the workload won't be used.
New stress test data specifically on RAM calls should be conducted to specify this consumption profile.
Determining the parameters
To determine a we averaged the electrical consumption of RAM per GB. With the process we came up with a=0.284
Capacity is either given by the user or the default value is used.
consumption_profile(workload) = 0.284 * capacity