Android Question KeyValueStore2 and Android Things

[fbritop]

I could not find where my AT app got stucked, after putting a lot of LOG Flags, I found out that

Public Sub Put(Key As String, Value As Object)

And KVS2 Class takes an enormous ammount of time to execute (from 3 to 7 seconds) to store a single Integer Value. But usualy it stores a small JSON Map

I cannot find out if the problem is with SQL or B4XSerializator.

Is there any precautions I should take when using KVS2 under RPI with AT?

Thanks
FBP

 

[Erel]

What is the output of:

Dim n As Long = DateTime.Now
kvs2.Put("test", 100)
Log($"Time1: ${DateTime.Now - n}"$")
n = DateTime.Now
File.WriteString(File.DirInternal, "test", "test")
Log($"Time2: ${DateTime.Now - n}"$")

?

 

[fbritop]

Erel,
Before your request i did some tests yesterday. I somehow managed to narrow down the problem to the line

sql1.ExecNonQuery2("INSERT OR REPLACE INTO main VALUES(?, ?)", Array (Key, ser.ConvertObjectToBytes(Value)))

Putting your same logic of dateTime.now differences. That was the point where de delay was. I thought it could be related to B4XSerializator so I changed it for testing to

sql1.ExecNonQuery2("INSERT OR REPLACE INTO main VALUES(?, ?)", Array (Key, Value))

With the same results. Then it was SQL, or somehow write disk operations. I'm an advance SQL Server user, but I have no clues about efficiency or performance regarding SQLLite, but I changed INSERT OR REPLACE and the problem was solved. By code now looks as:

    Try
        Dim ahora As Long = DateTime.Now
        
        Dim rs As ResultSet = sql1.ExecQuery2("SELECT value FROM main WHERE key = ?", Array As String(Key))
        If rs.NextRow Then
            sql1.ExecNonQuery2("update main set value=? where key=?", Array (Key, ser.ConvertObjectToBytes(Value)))
        Else   
            sql1.ExecNonQuery2("INSERT INTO main VALUES(?, ?)", Array (Key, ser.ConvertObjectToBytes(Value)))
        End If
        rs.Close
        'sql1.ExecNonQuery2("INSERT OR REPLACE INTO main VALUES(?, ?)", Array (Key, ser.ConvertObjectToBytes(Value)))
        Log("KEY:" & Key & " " & (DateTime.Now-ahora))
    Catch
        Log("KVS:ERROR.PUT:" & Key)
        Log(LastException)
    End Try

Not shure where the bookneck is whith SQLLite

 

[OliverA]

ql1.ExecNonQuery2("update main set value=? where key=?", Array (Key, ser.ConvertObjectToBytes(Value)))

There is a slight logic error here. Your array needs to be

Array (ser.ConvertObjectToBytes(Value), Key)

Update: That may change your timing again, since before (with the original array) it never performed any updates

 

[fbritop]

What is the output of:

Dim n As Long = DateTime.Now
kvs2.Put("test", 100)
Log($"Time1: ${DateTime.Now - n}"$")
n = DateTime.Now
File.WriteString(File.DirInternal, "test", "test")
Log($"Time2: ${DateTime.Now - n}"$")

?

Time1: 1334
Time2: 1

 

[Erel]

Strange results. Worth making tests with SQL to see whether it is consistent or not.

 

[fbritop]

Narrow down the problem, it only does happen when in the same sub there is a Timer Enable True, even thow I use Sleep(0). I use a lot of timers because of 8 different relays that I need to control