STA is taking quite a while on recent version

Question

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

Anton Blanchard · Answer

I haven t been able to reproduce it with upstream OpenROAD perhaps it s been fixed

Matt Liberty · Answer

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

Anton Blanchard · Answer

< U018LA3KZCJ> Yeah something doesn t add up Trying to get a test case together

Anton Blanchard · Answer

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

Anton Blanchard · Answer

< 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