We have been collecting Google Analytics for more than a year on VIAF, and it has been interesting tracking usage. Over the last year we had over a million page-views from Web browsers (Google Analytics depends on Web browsers executing code we put on our pages to collect statistics). VIAF's current activity is triple what it was a year ago and growing, so that number should rise.
However we are seeing much more activity from accesses that do not show up in VIAF's Google Analytics numbers. Direct access to VIAF not from browsers is about 90% of the activity, well over a million searches per month. About a million of those searches each month are the equivalent of a page-view.
It is not easy to completly understand the requests. Some of it is clearly Web spiders harvesting pages, other activity looks like people trying to match all their names against VIAF. Much of it could probably done in simpler ways, so if you are planning on throwing a few hundred thousand requests at VIAF, contact us. We'd like to know how you are using VIAF and may be able to offer suggestions on how to do it.
Based on our load tests, we don't think we are getting close to our performance limits. So far everyone seems to be acting quite responsibly (e.g. by sending us less than one search/second).
One of the things I was interested to see was how many requests are to VIAF's auto-suggest service. We have about three auto-suggest requests for each browser-originated search, which seems reasonable and on the low side of what I would expect.
We are very pleased with these numbers.