`DatabaseStore` incurs a high performance overhead (~10x)

[adamchainz]

After the 6.0 upgrade, I tried out the new DatabaseStore on a client project. On a page with hundreds of queries, the page load goes from a few seconds to about 30 seconds, on a fairly modern laptop. I'm sorry I don't have more information at this time, but it seems that some profiling is required to minimize the cost.

[tim-schilling]

@adamchainz to confirm, the baseline is with the memory store correct? We've seen that type of increase in just using the toolbar in the past when queries are egregious.

[adamchainz]

Yes, the baseline is against the memory store, rather than against disabling the toolbar.