fs_event_handler callback is delayed

[Sawada]

It takes time for fs_event_handler to be called back after nrf_fstorage_erase is executed.

In SDK13.1.0, it didn't take much time, but in SDK15.3.0 currently being developed, it takes time to be called back.

The priority cannot be set in the fstorage config of SDK15.3.0.
It is assumed that there is a delay due to not setting here.

*SDK13.1.0 
    FS_REGISTER_CFG(fs_config_t fs_config) =
    {
        .callback = fs_event_handler,
        .num_pages = PDL_PAGE_NUM,
        // We register with the highest priority in order to be assigned
        // the pages with the highest memory address (closest to the bootloader).
        .priority = 0xFE //***************this config*****************//
    };

*SDK15.3.0
    NRF_FSTORAGE_DEF(nrf_fstorage_t fs_mainte_config) =
    {
        .evt_handler = fs_event_handler,
        .start_addr = 0xD5000,
        .end_addr = 0xF6000,
    };

[Sawada]

Is there any alternative to "priority" in 15.3.0?

[Susheel Nuguru]

no, there does not seem to priority concept in fstorage, 

Do you know what is the context priority in which you are calling nrf_fstorage_erase? are you calling it from main thread or some interrupt priority? Can you also post us the difference in the time it takes between SDK13.1 and SDK15.3.

[Sawada]

>>Do you know what is the context priority in which you are calling nrf_fstorage_erase? 

No.

Immediately after the main thread started, we called the following in each SDK version and measured the time until the handler was executed.

SDK15.3: nrf_fstorage_erase()
-> 4 second
SDK13.1: fs_erase()
->0.2 second

[Susheel Nuguru]

Since there is no concept of priority now in fstorage, the call will inherit the priority of the caller, so the timing must have changed in your app.

which version of fstorage backend instance are you using?

If you are using NVMC, then we can try to bump up the priority by using EGU interrupt and make sure that your fstorage call is executed in a bit higher priority.

[Sawada]

I used "nrf_fstorage_sd.c".