Backup Test block selection logic

drwtsn32 · April 2, 2020, 5:18am

It is random, but the list of files to test is selected from three groups in this preference order:

Files that have never been tested
If more samples need testing (depending on settings), then select from files that have been tested before, with preference towards ones that have been tested less
If still more samples are needed to test, then choose from files that have been tested the most.

Here’s the code if you’re curious:

duplicati/duplicati/blob/master/Duplicati/Library/Main/Database/LocalTestDatabase.cs#L60


    public RemoteVolume(System.Data.IDataReader rd)

    {

        this.ID = rd.GetInt64(0);

        this.Name = rd.GetString(1);

        this.Size = rd.ConvertValueToInt64(2);

        this.Hash = rd.ConvertValueToString(3);

        this.VerificationCount = rd.ConvertValueToInt64(4);

    }

}



private IEnumerable<RemoteVolume> FilterByVerificationCount(IEnumerable<RemoteVolume> volumes, long samples, long maxverification)

{

    var rnd = new Random();



    // First round is the new items            

    var res = (from n in volumes where n.VerificationCount == 0 select n).ToList();

    while (res.Count > samples)

        res.RemoveAt(rnd.Next(0, res.Count));

    

    // Quick exit if we are done

    if (res.Count == samples)