Serialization when saving a large tree. Workaround is to use FsPickler

[fwaris]

Saving a

    let t1 =  new KdTree<float, Alrm>(1, new DoubleMath());
    t1.SaveToFile(@"D:\alarms\alarmIndex.bin")

Gives the following error with about 7M entries:
System.Runtime.Serialization.SerializationException: The internal array cannot expand to greater than Int32.MaxValue elements.
at System.Runtime.Serialization.ObjectIDGenerator.Rehash()
at System.Runtime.Serialization.ObjectIDGenerator.GetId(Object obj, Boolean& firstTime)

However this worked for both saving and loading:

    let ser = MBrace.FsPickler.BinarySerializer()
    ser.Serialize(IO.File.Create @"D:\alarms\alarmIndex.bin", t1)
    let t2:KdTree<float, Alrm> = ser.Deserialize(IO.File.OpenRead @"D:\alarms\alarmIndex.bin")

Maybe you can switch to FsPickler internally for serialization