sftpfs: reuse connections

Signed-off-by: Nicola Murino <nicola.murino@gmail.com>

internal/vfs/azblobfs.go

@@ -566,6 +566,9 @@ func (fs *AzureBlobFs) ScanRootDirContents() (int, int64, error) {
 				}
 				numFiles++
 				size += blobSize
+				if numFiles%1000 == 0 {
+					fsLog(fs, logger.LevelDebug, "root dir scan in progress, files: %d, size: %d", numFiles, size)
+				}
 			}
 		}
 	}