We received access to a Google Storage for Developers account today, and being the curious types, immediately ran some network tests. We maintain a network of about 40 cloud servers around the world which we use to monitor cloud servers, test cloud-to-cloud network throughput, and our cloud speedtest. We used a handful of these to test Google Storage uplink and downlink throughput and latency. We were very surprised by the low latency and consistently fast downlink throughput to most locations.
Most storage services like Amazon’s S3 and Azure Blob Storage are physically hosted from a single geographical location. S3 for example, is divided into 4 regions, US West, US East, EU West and APAC. If you store a file to an S3 US West bucket, it is not replicated to the other regions, and can only be downloaded from that regions’ servers. The result is much slower network performance from locations with poor connectivity to that region. Hence, you need to chose your S3 region wisely based on geographical and/or network proximity. Azure’s Blob storage uses a similar approach. Users are able to add CDN on top of those services (CloudFront and Azure CDN), but the CDN does not provide the same access control and consistency features of the storage service.
In contrast, Google’s new Storage for Developers service appears to store uploaded files to a globally distributed network of servers. When a file is requested, Google uses some DNS magic to direct a user to a server that will provide the fastest access to that file. This is very similar to the approach that Content Delivery Networks like Akamai and Edgecast work, wherein files are distributed to multiple globally placed PoPs (point-of-presence).
Our simple test consisted of requesting a test 10MB file from 17 different servers located in the US, EU and APAC. The test file was set to public and we used wget to test downlink and Google’s gsutil to test uplink throughput (wget was faster than gsutil for downloads). In doing so, we found the same test URL resolved to 11 different Google servers with an average downlink of about 40 Mb/s! This hybrid model of CDN-like performance with enterprise storage features like durability, consistency and access control represents an exciting leap forward for cloud storage!
Google Storage Network Performance Tests
|Service||Location||Resolved To||Latency||Upload (Mb/s)||Download (Mb/s)|
|EC2 (EU West)||Ireland||188.8.131.52||2.19||6.58||29.5|
|Rimu Hosting||New Zealand||184.108.40.206||27.05||5.53||9.64|
|Gandi Cloud VPS||France||220.127.116.11||19.9||2.81||31.1|
|Voxel (Amsterdam)||The Netherlands||18.104.22.168||83.2||3.86||40.6|
|EC2 (US East)||VA, US||22.214.171.124||2.72||10.14||39.4|
|EC2 (US West)||VA, US||126.96.36.199||27.7||8.77||9.5|
|Rackspace (Chicago)||IL, US||188.8.131.52||13.05||4.23||70.3|