diff --git a/platformio.ini b/platformio.ini
index 901b652a..7e0c3df9 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -21,6 +21,7 @@ board_upload.offset_address = 0x10000
 
 build_flags =
   -DARDUINO_USB_MODE=1
+  -DMAINTAIN_FREE_CLUSTER_COUNT=1 ; let sdFat cache cluster count data to speed up free space calculations
   -DARDUINO_USB_CDC_ON_BOOT=1
   -DEINK_DISPLAY_SINGLE_BUFFER_MODE=1
   -DDISABLE_FS_H_WARNING=1