open-source-silicon.dev

<@U018LA3KZCJ> STA is taking quite a while on recent versions of openlane. A quick profile shows almost all time in `odb::_dbModule::removeInst`:

I haven't been able to reproduce it with upstream OpenROAD, perhaps it's been fixed

STA doesn't remove instances so something doesn't add up.  That API did come up in another context as needing to be sped up but nothing has happened yet

<@U018LA3KZCJ> Yeah something doesn't add up. Trying to get a test case together

I think part of the issue is we are doing 3x more STA runs as a result of <https://github.com/The-OpenROAD-Project/OpenLane/commit/b73708657657af6c1d7626ff8d390adc982627db#diff-4e5e255b90b9cb5c3f310f50e7288773831377ffdc3bf60b7331680fc23ab541R82|https://github.com/The-OpenROAD-Project/OpenLane/commit/b73708657657af6c1d7626ff8d390adc982627db#diff-4e5e255b90b9cb5c3f3[…]bf60b7331680fc23ab541R82>
For each min/nom/max SPEF corner, we run a multi corner STA with ss/tt/ff liberty, so 9 corners.

<@U020J2W6Q84> doing all corner STA runs in parallel would be a nice optimisation. I'm not sure how easy it is to do in TCL though