Siemens Business Services, Internet Operations have kindly provided us with some statistics and graphs of server output covering the 7th July.
- Webserver statistics. Including: total bandwidth, page impressions per second and use of streaming media
- Use of multicast technologies
- At peak times during the day there were 40,000 page requests per second from News
- Total maximum bandwidth from bbc.co.uk reached: 11.1Gb/s (In addition to this there was up to 3Gb/sec going to Akamai for News - http://news.bbc.co.uk/2/hi/technology/4663423.stm)
The following two graphs show the total bandwidth across the BBC webservers. Time on both of these runs from left to right.
At around 12 noon on the 7th July, a peak bandwidth of over 11 gigabits/sec was reached. The slight disparity between the two "Max Out" values is caused the load affecting recording statistics
The previous day's announcement of 2012 Olympics being awarded to London caused a peak of around 5 gigabits/second. The previous all time high was caused by the announcement of the Michael Jackson verdict, which used 7.2 gigabits/second
The next couple of graphs show the use of online media streams. There is a rise from just under 20,000 users to over 120,000 in a couple of hours. Please note that time runs right to left on these graphs.
Maximum total concurrent streams: 129,000 (peak was between 2pm and 3pm) Prior to this the maximum number of concurrent streams was 74,000 streams, again on the night of The Michael Jackson announcement .
For most of the afternoon we held steady at 110,000 concurrent streams until 5.30pm/6.00pm when things started to drop off.
Windows Media Player
Hits per second on 3 of the webservers
These final graphs are a sample of the hit rate statistics from three of our webservers. The peak number of pages served by each of these was about 500 pages per second or 1.8 million per hour. At the current time we cannot provide detailed information on the number of unique users but hope to be able to do so in the near future once we have done full log analysis.
The gaps in these graphs are caused not caused by server downtime, rather that the servers were busy serving.
At normal times the multicast trials are restricted to a number of UK ISPs. This is to make sure that only people within the UK can access the streams. The reasons behind this restriction are mainly due to broadcast rights and the fact the BBC is funded by the TV licence fee.
However yesterday at approximately 9.45am we removed the access control to the unicast stream of BBC News 24. The aim was to provide news access whilst promoting the sort of quality people can get if they ask their ISP to enable multicast.
Hopefully as more ISPs join the trial* we can use it to help cope with large demands for streaming in the future.
For an explanation of why the BBC is trialing multicast technologies please visit http://support.bbc.co.uk/multicast/why.html