Maximum number of records per file ?

[QuentinFarizon]

I am writing 3305 records into a single FDS "file" (0x1000)

But when looping through them with `while ((err_code = fds_record_find_in_file(data_type_to_file_id(data_type), &record_desc, &find_token)) == NRF_SUCCESS) {` it loops through only 2304 records.
For the last one, err_code is FDS_ERR_NOT_FOUND, exactly like if there was no more records in this file.

For the first 2304, I have no issue retrieving, writing, updating them, ...

I have launched my program several times, it always loops through 2304 records. Is this a known limit of maximum number of records for one file ?

Code :

    ret_code_t err_code;
    fds_flash_record_t flash_record;
    fds_record_desc_t record_desc;

    fds_find_token_t find_token;
    memset(&find_token, 0x00, sizeof(fds_find_token_t));


    while ((err_code = fds_record_find_in_file(data_type_to_file_id(data_type), &record_desc, &find_token)) == NRF_SUCCESS) {
        < check record >
    }

[Einar Thorsrud]

Hi,

There is no defined maximum number. You can even have multiple records with the same ID within the same file.

Are you sure the additional records are there? Could it be that records after number 2304 are not written for some reason? Perhaps because of no more room in FDS, or some other reason, but you fail to handle an error that occurred before so that it failed silently so that it is not notices before attempting to read?

[QuentinFarizon]

Yes, I am checking errors while writing, and I have logs confirming they are all written

[Einar Thorsrud]

Can you upload an application that I can run on the DK to see this failing on my end (along with instructions on how to reproduce the issue with it)?

[QuentinFarizon]

Ok this was tricky to debug. To see correctly the writing process I added a 1 ms delay (nrf_delay_ms(1)) between each write (if I don't do that I lose RTT output)

But in fact this 1 ms delay "fixed" the issue, so I guess there is something wrong when making several FDS write too quickly

Note that for each write I wait for the FDS_EVT_WRITE before proceeding to the next write.

Any idea why this 1ms delay is necessary ?

[Einar Thorsrud]

It should not be possible to write too fast as long as you wait for the previous operation to finish (even that is not needed as FDS has an operation queue that can hold multiple operations, though if this fills up and you get FDS_ERR_NO_SPACE_IN_QUEUES returned from FDS API calls, you will need to wait).