Hi!
>>>>> "Peter" == Peter Zaitsev <[EMAIL PROTECTED]> writes:
Peter> Hello mysql,
Peter> Today I played a little bit with two different ways of backup -
Peter> first one is to use BACKUP TABLE (which works for myisam only) and
Peter> the second one is SAVE DATA/LOAD DATA.
Peter> In both cases if I'm not mistaken the file is wrote by mysqld server
Peter> so there is no communication overhead.
Peter> The table was about 3mil of rows 250MB in size, has 2 indexes.
Peter> So the speeds are:
Peter> BACKUP TABLE:
Peter> backup: 26sec restore: 3min.15sec
Peter> SAVE DATA/LOAD DATA
Peter> dump: 4.5min restore: 40min
What was the exact commands you used?
Peter> Then I tried to drop all indexes from the table and tried to do
Peter> restore again it went in: 31min
Could you show you exactly how you did this!
Peter> The output from backup was 250MB, save file - 400MB.
Peter> These speeds was really strange for me, I did't expect so huge
Peter> difference in speads, as I don't see there it should get from. The
Peter> save data outfile operation should be quite fast as the speed of
Peter> text parsing should be the real limit, also the really surprising
Peter> was so slow speed of import data from text, even with no indexes on
Peter> the table if we would look at the speed it's only about 1000 rows
Peter> per second which is quite slow.
The main difference between RESTORE TABLE and LOAD DATA is that
RESTORE DATA is doing a binary copy of the data while LOAD DATA reads
and parses a text file. I would however had guessed that the
LOAD wouldn't have been more than 20 % slower than RESTORE
because it should be disk bound.
Any change you could dump the table to 'secret' with the exact command
you used, so that we could try to repeat this?
Regards,
Monty
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