> Seems pretty much buggy!!!
What "bugs"? Error reports from the mysql error log please.
> load database very slow
You mean how long it takes the commandline MySQL client program to execute the USE command, or the time it takes phpMyAdmin to populate its table display after you select a database from its databae droprown?
> No fix table on row
What does that mean?
> Can upgrade the new mysql version without reinstalling?
Upgrade requires backup plus installation plus database touchups. It's unlikely to fix your issues with slowness, which you should address before you upgrade.
How much RAM does the machine have? What proportion of that RAM is available to MySQL. Is there swapping? Let's see the result of ...
SELECT
IFNULL(B.engine,'Total') "Storage Engine",
CONCAT( LPAD(REPLACE(FORMAT(B.DSize/POWER(1024,pw),3),',',''),17,' '), ' ',
SUBSTR(' KMGTP',pw+1,1),'B'
) "Data Size",
CONCAT( LPAD(REPLACE(FORMAT(B.ISize/POWER(1024,pw),3),',',''),17,' '), ' ',
SUBSTR(' KMGTP',pw+1,1),'B'
) "Index Size",
CONCAT( LPAD(REPLACE(FORMAT(B.TSize/POWER(1024,pw),3),',',''),17,' '), ' ',
SUBSTR(' KMGTP',pw+1,1),'B'
) "Table Size"
FROM (
SELECT
engine,
SUM(data_length) DSize,
SUM(index_length) ISize,
SUM(data_length+index_length) TSize
FROM information_schema.tables
WHERE table_schema NOT IN('mysql','information_schema','performance_schema')
AND engine IS NOT NULL
GROUP BY engine WITH ROLLUP
) B,
(SELECT 3 pw) A
ORDER BY TSize;
And let's see the results of ...
show variables;
show global status;