improve vram safety with 5% vram memory buffer (#724)

* check free memory not total
* wait for subprocess to exit
This commit is contained in:
Bruce MacDonald 2023-10-10 16:16:09 -04:00 committed by GitHub
parent 65dcd0ce35
commit f2ba1311aa
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23

View file

@ -191,7 +191,7 @@ var errNoGPU = errors.New("nvidia-smi command failed")
// CheckVRAM returns the available VRAM in MiB on Linux machines with NVIDIA GPUs
func CheckVRAM() (int64, error) {
cmd := exec.Command("nvidia-smi", "--query-gpu=memory.total", "--format=csv,noheader,nounits")
cmd := exec.Command("nvidia-smi", "--query-gpu=memory.free", "--format=csv,noheader,nounits")
var stdout bytes.Buffer
cmd.Stdout = &stdout
err := cmd.Run()
@ -199,7 +199,7 @@ func CheckVRAM() (int64, error) {
return 0, errNoGPU
}
var total int64
var free int64
scanner := bufio.NewScanner(&stdout)
for scanner.Scan() {
line := scanner.Text()
@ -208,10 +208,10 @@ func CheckVRAM() (int64, error) {
return 0, fmt.Errorf("failed to parse available VRAM: %v", err)
}
total += vram
free += vram
}
return total, nil
return free, nil
}
func NumGPU(numLayer, fileSizeBytes int64, opts api.Options) int {
@ -228,14 +228,14 @@ func NumGPU(numLayer, fileSizeBytes int64, opts api.Options) int {
return 0
}
totalVramBytes := int64(vramMib) * 1024 * 1024 // 1 MiB = 1024^2 bytes
freeVramBytes := int64(vramMib) * 1024 * 1024 // 1 MiB = 1024^2 bytes
// Calculate bytes per layer
// TODO: this is a rough heuristic, better would be to calculate this based on number of layers and context size
bytesPerLayer := fileSizeBytes / numLayer
// max number of layers we can fit in VRAM
layers := int(totalVramBytes / bytesPerLayer)
// max number of layers we can fit in VRAM, subtract 5% to prevent consuming all available VRAM and running out of memory
layers := int(freeVramBytes/bytesPerLayer) * 95 / 100
log.Printf("%d MiB VRAM available, loading up to %d GPU layers", vramMib, layers)
return layers
@ -367,7 +367,13 @@ func waitForServer(llm *llama) error {
}
func (llm *llama) Close() {
// signal the sub-process to terminate
llm.Cancel()
// wait for the command to exit to prevent race conditions with the next run
if err := llm.Cmd.Wait(); err != nil {
log.Printf("llama runner exited: %v", err)
}
}
func (llm *llama) SetOptions(opts api.Options) {