server: add dynamic configuration for download variables

server/download.go

@@ -25,7 +25,11 @@ import (
 	"github.com/ollama/ollama/format"
 )
 
-const maxRetries = 6
+// env-tweakable constants
+var maxRetries = getEnvInt("OLLAMA_DOWNLOAD_RETRIES", 6)
+var numDownloadParts = getEnvInt("OLLAMA_DOWNLOAD_PARALLEL", 64)
+var minDownloadPartSize = getEnvInt("OLLAMA_DOWNLOAD_MIN_SIZE", int64(100*format.MegaByte))
+var maxDownloadPartSize = getEnvInt("OLLAMA_DOWNLOAD_MAX_SIZE", int64(1000*format.MegaByte))
 
 var errMaxRetriesExceeded = errors.New("max retries exceeded")
 var errPartStalled = errors.New("part stalled")
@@ -58,12 +62,6 @@ type blobDownloadPart struct {
 	*blobDownload `json:"-"`
 }
 
-const (
-	numDownloadParts          = 64
-	minDownloadPartSize int64 = 100 * format.MegaByte
-	maxDownloadPartSize int64 = 1000 * format.MegaByte
-)
-
 func (p *blobDownloadPart) Name() string {
 	return strings.Join([]string{
 		p.blobDownload.Name, "partial", strconv.Itoa(p.N),
@@ -111,7 +109,7 @@ func (b *blobDownload) Prepare(ctx context.Context, requestURL *url.URL, opts *r
 
 		b.Total, _ = strconv.ParseInt(resp.Header.Get("Content-Length"), 10, 64)
 
-		size := b.Total / numDownloadParts
+		size := b.Total / int64(numDownloadParts)
 		switch {
 		case size < minDownloadPartSize:
 			size = minDownloadPartSize

server/images.go

@@ -33,6 +33,8 @@ import (
 	"github.com/ollama/ollama/version"
 )
 
+var maxDigestRetries = getEnvInt("OLLAMA_DOWNLOAD_DIGEST_RETRIES", 3)
+
 type registryOptions struct {
 	Insecure bool
 	Username string
@@ -1266,10 +1268,13 @@ func verifyBlob(digest string) error {
 	}
 	defer f.Close()
 
-	fileDigest, _ := GetSHA256Digest(f)
-	if digest != fileDigest {
-		return fmt.Errorf("%w: want %s, got %s", errDigestMismatch, digest, fileDigest)
+	for i := 0; i < maxDigestRetries; i++ {
+		fileDigest, _ := GetSHA256Digest(f)
+		if digest == fileDigest {
+			return nil
+		}
+		err = fmt.Errorf("%w: want %s, got %s", errDigestMismatch, digest, fileDigest)
+		slog.Warn(err.Error())
 	}
-
-	return nil
+	return err
 }

server/util.go

@@ -0,0 +1,27 @@
+package server
+
+import (
+	"os"
+	"strconv"
+	"unsafe"
+)
+
+type Int interface {
+	int | int8 | int16 | int32 | int64
+}
+
+func parseInt[T Int](v string, fallback T) T {
+	i, err := strconv.ParseInt(v, 10, int(unsafe.Sizeof(fallback)))
+	if err != nil {
+		return fallback
+	}
+	return T(i)
+}
+
+func getEnvInt[T Int](key string, fallback T) T {
+	v, ok := os.LookupEnv(key)
+	if !ok {
+		return fallback
+	}
+	return parseInt(v, fallback)
+}