It also makes all new readers/writers to wait for that lock, essentially leading to downtime until the lock is eventually acquired and released. This is the cla

It also makes all new readers/writers to wait for that lock, essentially leading to downtime until the lock is eventually acquired and released. This is the classic readers/writers library example, and you want to avoid starving the writers. Thats why size of data is the least of your issues - its the access patterns/hotness that are the issue.