get_available_ram

get_available_ram

SYSTEM_UTILS

1 Description

Returns the amount of RAM currently available for allocation.

2 Usage

get_available_ram()

3 Value

Numeric value with available RAM in gigabytes (GB)

4 Details

This function returns the RAM that can be allocated without swapping. The value changes dynamically as processes allocate and free memory.

Important notes: - Value can change rapidly; don’t cache it - On Linux, uses MemAvailable (more accurate than MemFree) - Includes memory that can be reclaimed from caches - Actual allocatable memory may be slightly less

Use case: Check available RAM before loading large datasets into memory.

5 Examples

\donttest{
available <- get_available_ram()
cat("Available RAM:", round(available, 2), "GB\n")

# Use it to decide how much data to load
fn <- tempfile(fileext = ".h5")
X  <- hdf5_create_matrix(fn, "data/M",
                          data = matrix(rnorm(1000), 100, 10))

size_gb <- prod(dim(X)) * 8 / 1e9
if (get_available_ram() > size_gb * 1.2) {
  mat <- as.matrix(X)
} else {
  mat <- X[1:50, ]
}

hdf5_close_all()
unlink(fn)
}

6 See Also

get_total_ram, can_allocate

---
title: "get_available_ram"
subtitle: "get_available_ram"
---

<span class="category-badge system_utils">SYSTEM_UTILS</span>

## Description

Returns the amount of RAM currently available for allocation.

## Usage

```r
get_available_ram()
```
## Value

::: {.return-value}
Numeric value with available RAM in gigabytes (GB)

:::
## Details

This function returns the RAM that can be allocated without swapping.
The value changes dynamically as processes allocate and free memory.

**Important notes:**
- Value can change rapidly; don't cache it
- On Linux, uses MemAvailable (more accurate than MemFree)
- Includes memory that can be reclaimed from caches
- Actual allocatable memory may be slightly less

**Use case:**
Check available RAM before loading large datasets into memory.

## Examples
```{r}
#| eval: false
#| warning: false

\donttest{
available <- get_available_ram()
cat("Available RAM:", round(available, 2), "GB\n")

# Use it to decide how much data to load
fn <- tempfile(fileext = ".h5")
X  <- hdf5_create_matrix(fn, "data/M",
                          data = matrix(rnorm(1000), 100, 10))

size_gb <- prod(dim(X)) * 8 / 1e9
if (get_available_ram() > size_gb * 1.2) {
  mat <- as.matrix(X)
} else {
  mat <- X[1:50, ]
}

hdf5_close_all()
unlink(fn)
}

```
## See Also

::: {.see-also}
[get_total_ram](get_total_ram.html), [can_allocate](can_allocate.html)

:::