before or after?

if u trying to update only one row, everything ok?

so I can explain, that in current code that you show you trying to make all 20k updates at absolutly same time in 20k parralell threads, so I think its dont gave to breath nodejs and prisma I recommeded to you look at prisma.updateMany fn or looking to some flow managing library like

async.js

and do to run your threads one by one, or

async.forEachLimit

with limited +-10 threads

updateMany will generates for you one large query to db, than prisma send id to db, and then loooong proceed from inside db. but just in one thread and single function call ah also you can

_.chunk

you array by 100 items and then proceed