I encountered performance issues with 6.10 that I didn’t experience in 6.9, as discussed here:
PL6.10.0 maxing out the processor on Win 10 when working on an image - #5 by SAFC01.
In another thread, DxO identified an issue that might be the explanation, and could be the cause of your problems.
https://forum.dxo.com/t/new-plv6-9-0-build-267-is-very-slow-compared-to-former-version/34567/10#:~:text=Hello%2C%0AWe,Best%20regards