Google Cloud Storage pricing question - multi-region vs dual-region

[vitaly_il]

According to Google docs and examples,
- for dual-region we pay twice (i.e. we pay for 1TB in both regions )

- but for multi-region we don't pay 3 times 

Is it right (if yes, why?) or I'm missing something?

Thanks, Vitaly
https://cloud.google.com/storage/pricing
https://cloud.google.com/storage/pricing-examples#detailed

[KirTitievsky · Accepted solution]

Vitaly, that's correct.  You pay once for multi-region. In fact, multi-region storage is cheaper than dual region.  This is because multi-region allows gives us flexibility to place the data most efficiently among all our data centers in the region.   Also, you will pay egress fees when reading data from a multi-region bucket (unless you are copying data from one GCS bucket to another within the multi-region).  But with a dual region, there is no egress fee when you read the data from one of the two regions included in the bucket location.   So in a way, you are trading off cheaper storage for more expensive IO between multi and dual region locations. Does that help?

[vitaly_il]

Thank you!

>  you will pay egress fees when reading data from a multi-region bucket

Even if I read from the same region?

[KirTitievsky]

There are only a couple ways I know to "read from the same region."  One is if you copy a file from US MR to US MR.  But if you are running a client on a machine in, say, us-west1 it is not in the same location as your data. The data is in the location called "US" and the machine is in a location called "us-west1."  They are not the same location.     You are right that it is possible that the machine and the bits on disk are may be in the same region. But this is not something that is guaranteed. So we treat MR and single regions as different locations. That's why a distinction is made between a GCS location (e.g. US MR) and a GCP region. 

[vitaly_il]

Thank you again! 
I see, probably I should RTFM for understanding GCP geolocations better.

[kthegeek]

How is the egress charged if the requests are coming from  Media CDN to a Multi region bucket ?