Performance

To evaluate performance, this example only allows conditional statements, because too many aspects are involved, especially the variety used as a cached gateway, with its sophisticated technologies that ensure synchronization in the background does not affect iSCSI performance. The performance is, of course, only as good or bad as the connection to the Internet (as far as the AWS site is concerned) and the underlying iSCSI connection to the host, implemented in the setup here with a VM kernel adapter at 1Gbps without multipathing.

Some test runs with classic Iometer workloads [1] on a VM filesystem (VMFS) datastore "cached" with AWS storage produced results that are not noticeably different from those with locally connected storage. With the underlying architecture described as 1x1Gbps to the iSCSI adapter with asynchronous DSL (89Mbps downstream, 32Mbps upstream copper/vectoring), the Exchange_64 workload (60 percent Read, 0 Random) achieved the following results:

*743.27 Read IOPS

*384.84 Write IOPS

*46.45Mbps Read

*24.95Mbps Write

These results are far from enterprise values but are in line with what could be expected from the underlying infrastructure.

Conclusions

AWS Storage Gateway allows effective use of S3 storage with local applications or workflows via the standard iSCSI and NFS protocols, making any adjustments to applications a thing of the past. Local cache and other technologies, such as intelligent buffering, upload management, network fluctuations, and bandwidth management, ensure sufficient performance.

Because the gateway is stateless, you can easily create new instances of your gateways as needed, and the gateway can also be natively integrated with AWS management services such as Amazon CloudWatch, AWS CloudTrail, AWS KMS, and IAM.

For companies that already use AWS resources on a large scale, the gateway is a very convenient way to simplify integration with local resources. However, anyone who considers the service a welcome ticket to cloud computing for the use of S3 with all its features from existing applications and workflows must be cautious in view of the complex pricing, as is usual with AWS. All this fun is not cheap, and if you do not have a long-term AWS strategy, you will probably also find cheaper ways to use cloud storage on the free market.