问题
Let's say a code running in Region A publishes a message. Can cloud function in region B and C subscribe for such events?
回答1:
In standard, YES. Pubsub is a global service. If the publisher and the subscriber are in the same region, there is no reason the message change region.
But in cross region, the message is forwarded to the subscriber region and then consumed. You don't see this mechanism, it's automatic and managed by PubSub
However, if you have legal constrains, you can limit the available regions for PubSUb
来源：https://stackoverflow.com/questions/65053230/is-gcp-pub-sub-region-specific