Export Slows As It Progresses

[expired user #9271]'s profile image [expired user #9271] posted 7 years ago in Import/Export Permalink

I have a SQL DB that I export to a local MySQL instance on my development machine regularly. The export starts out screaming fast but as it progresses the processes slows to a crawl.

This is not caused by larger tables later in the update because if I shut down and restart HeidiSQL and start the export at a large table it's fast again.

For now I am resorting to doing several exports selecting just a few tables at a time but this "feels" like a bug to me, perhaps a memory leak? Monitoring HeidiSQL's memory usage during an export the usage bounces all over but get's quite high (up to 2GB at times).

I've tried adjusting the export settings, changing the max insert size up and down, and nothing seems to improve the performance degradation.

This issue shows up regardless of the source and destination servers. I have three servers on my local network (one screaming 16-core, 32GB, SSD) but the issue shows up with all of them.

Has anyone else encountered this?

[expired user #9271]'s profile image [expired user #9271] posted 7 years ago Permalink

If I were to venture a guess I'd say the issue is a memory leak or memory management issue of some kind. I am exporting a single table with a size on disk of 727MB to a local MySQL instance. It started out quickly, getting to 20% in about 5 minutes It's taken well over 90 minutes to get to 85%.

Windows Task Manager initially showed memory usage of HeidiSQL maxing out at 300MB but now it is getting over 4GB and climbing. I've attached a screen shot showing a usage of 3.5GB. This shouldn't happen transferring a 727MB table, even if the table was completely loaded in memory first.

Hopefully someone on the HeidiSQL team will see my post and investigate.

1 attachment(s):
  • chrome_2017-04-21_11-45-18

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