Amazon's hosted Simple Queue Service (SQS) has had performance problems this month that have left users questioning its overall stability and viability for commercial applications.

The latest incident occurred on Monday, when SQS experienced increased error rates for about 35 minutes after an overloaded router triggered increased packet loss, according to Amazon's Service Health Dashboard for its Amazon Web Services cloud computing offerings.

Between September 9 and September 11, increased error rates also rocked SQS and, although Amazon restored the service's stability, the company didn't fully diagnose and fix the problem until September 18.

"The specific change we rolled out is in the way we handle garbage collection in the back-end message nodes. With the removal of this root cause, the Amazon SQS issues of September 9 to 11 have been addressed," Amazon wrote in the service dashboard on September 19, making reference to a system upgrade it had performed the day before.

In addition, SQS spit out an assortment of errors over several days in late August and early September, a situation that Amazon resolved on September 4, according to postings from SQS users and Amazon representatives in this thread in the service's official discussion forum.

Since last week, some SQS users have been sounding off on another thread titled "SQS is way too unreliable, what's going on?"

"This is nowhere near the kind of reliability I need from a service that I'm using as part of a production app. Can we get some sort of statement on what's going on? Without some kind of assurance that this will be resolved very soon I can't continue to use it," an SQS user identified as Paul Dowman wrote last week.

Amazon didn't immediately respond to a request for comment.

SQS is one of the hosted services that Amazon provides for developers via its Amazon Web Services (AWS) suite of generic computing, payment, billing, fulfilment and web search services.

AWS is part of a popular trend toward cloud computing offerings, in which vendors provide applications and IT infrastructure services via the Internet from their own data centres.

Cloud-based services and software offer customers an alternative to installing hardware and software on their own premises.

This cloud model, in theory, reduces hardware provisioning costs for clients and frees them from maintenance responsibilities.