Add debug logging for blob and delta size (authored by Claude)

Author: vraiti

image/copy/single.go

@@ -32,6 +32,20 @@ import (
 	chunkedToc "go.podman.io/storage/pkg/chunked/toc"
 )
 
+// formatSize formats a size in bytes with dynamic units (B, KB, MB, GB)
+func formatSize(size int64) string {
+	const unit = 1024
+	if size < unit {
+		return fmt.Sprintf("%d B", size)
+	}
+	div, exp := int64(unit), 0
+	for n := size / unit; n >= unit; n /= unit {
+		div *= unit
+		exp++
+	}
+	return fmt.Sprintf("%.1f %cB", float64(size)/float64(div), "KMGT"[exp])
+}
+
 // imageCopier tracks state specific to a single image (possibly an item of a manifest list)
 type imageCopier struct {
 	c                             *copier
@@ -804,6 +818,7 @@ func (ic *imageCopier) copyLayer(ctx context.Context, srcIndex int, srcInfo type
 			return types.BlobInfo{}, "", err
 		}
 		if deltaStream != nil {
+			logrus.Debugf("Applying delta for layer %s (delta size: %.1f MB)", deltaDiffID, float64(matchingDelta.Size)/(1024.0*1024.0))
 			bar, err := ic.c.createProgressBar(pool, false, matchingDelta, "delta", "done")
 			if err != nil {
 				return types.BlobInfo{}, "", err
@@ -990,6 +1005,8 @@ func (ic *imageCopier) copyLayer(ctx context.Context, srcIndex int, srcInfo type
 		}
 		defer srcStream.Close()
 
+		logrus.Debugf("Downloading layer %s (blob size: %s)", srcInfo.Digest, formatSize(srcBlobSize))
+
 		blobInfo, diffIDChan, err := ic.copyLayerFromStream(ctx, srcStream, types.BlobInfo{Digest: srcInfo.Digest, Size: srcBlobSize, MediaType: srcInfo.MediaType, Annotations: srcInfo.Annotations}, diffIDIsNeeded, toEncrypt, bar, srcIndex, emptyLayer)
 		if err != nil {
 			return types.BlobInfo{}, "", err