The 1901 census website, which contains searchable records for over 32 million people, is finally set to go back online after buckling under the initial demand.
Launched in January, the site was expecting to receive 1.2 million hits a day. It instead received more than one million hits an hour, and was unable to cope.
The Public Record Office (PRO) has been redesigning and testing it ever since.
Consultants QinetiQ, formerly part of the government-owned Defence and Evaluation Research Agency, told vnunet.com that the site will be ready to go live in the next "few weeks".
QinetiQ, which won the £7m contract in 1999, has shouldered the undisclosed extra costs for the enhancements. Although searches will remain free it plans to recoup money by charging for services such as downloading pictures and documents.
"QinetiQ has spent a number of months increasing the robustness and effectiveness with new hardware, software and functionality, and testing the service to ensure resilience," said a spokesman.
Limited numbers of users are currently testing the site at the PRO in Kew and the Family Records Centre in Farringdon so that usage behaviour can be monitored before it is relaunched nationwide.
Load testing software has successfully simulated volumes in excess of one million people an hour, and the site has coped with automated concurrent database searches equivalent to the population of a small town, according to QinetiQ.
Bandwidth has been increased by a factor of five, database capacity has been doubled and there are now dedicated instead of shared firewalls for the site.
QinetiQ admitted that user levels had been 30 times greater than the site had been designed for in January, but said that it can now cope.
If the search engine becomes overloaded this time, load management software will divert visitors to a static offline version of the site. This should ensure that the main census site does not crash under the demand.
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