fs_sync() getting stuck for around 200-400ms

[Mithilesh Yadav]

Hi, 

I am working on nrf52840dk's on board mx25r64 external flash for create files and write data into it. I am using "samples\subsys\usb\mass" sample code. I followed sequence for writing data into file is- fs_open()->fs_write()->fs_synce()->fs_close()  but i am experiencing a delay of around 200-400ms when using fs_sync(). I am using FATFS filesystem.

So my question is how i can decrease the synchronization times. The project configurations are:

CONFIG_STDOUT_CONSOLE=y

#USB related configs
CONFIG_USB_DEVICE_STACK=y
CONFIG_USB_DEVICE_PRODUCT="Zephyr MSC sample"
CONFIG_USB_DEVICE_PID=0x0008
CONFIG_LOG=y
CONFIG_USB_DRIVER_LOG_LEVEL_ERR=y
CONFIG_USB_MASS_STORAGE=y
CONFIG_USB_DEVICE_LOG_LEVEL_ERR=y
CONFIG_USB_MASS_STORAGE_LOG_LEVEL_ERR=y
CONFIG_USB_DEVICE_INITIALIZE_AT_BOOT=n

CONFIG_MAIN_STACK_SIZE=1536

CONFIG_APP_MSC_STORAGE_FLASH_FATFS=y
CONFIG_FS_FATFS_LFN=y

CONFIG_FILE_SYSTEM=y
CONFIG_FILE_SYSTEM_MKFS=y

Thanks.

[Turbo J]

Not unusual.

Secor erase time max is 240ms in datasheet for the memory chip, and you have to erase multiple sectors during the f_sync() call.

Note that the sync call is not really required if you call f_close() immidiately after.