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Re: Data Export and Import
Posted by: Peter Brawley
Date: July 27, 2021 09:26AM

Extended inserts done the way mysqldump does them can make big ram demands; 10h sounds a lot like swapping is going on.

3.8M rows isn't a lot. This is on a local MySQL instance? 10 hours is way way too long. On a modest modern machine we see row import rates of 35k/sec where average row size is 100 bytes. Is your system optimised? Is it on a modern machine with an SSD? Are the dump file and the DB on different drives? Is innodb_buffer_pool_size big_enough? Is there enough RAM for your load? Run the cheatsheet as described under that name at, fix what needs fixing.

Once all that's sorted, diagnose the bottleneck---prepare a subset of the problem table, then while it's importing, watch for swapping, watch engine innodb status, compare extended-inserts vs not, keep going till you have best performance.

If it's still too slow, then have a look at

[Edited to update typical dump import speeds]

Edited 1 time(s). Last edit at 07/27/2021 10:17AM by Peter Brawley.

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July 27, 2021 07:58AM
Re: Data Export and Import
July 27, 2021 09:26AM
July 27, 2021 11:03AM
July 27, 2021 01:12PM

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