Original URL: http://www.theregister.co.uk/2008/12/26/soho_rendering_supercomputer/

Getting animated about a 6,000 core Soho supercomputer

Can you get me 413,138 mouse hairs?

By Chris Mellor

Posted in Servers, 26th December 2008 08:02 GMT

London's Soho has become a thriving media rendering and animation centre, with creative media professionals using the latest model IT gear in shiny studios between buildings full of 'models' selling the oldest professional services of all.

Framestore is one of these new companies bolstering Soho's image. It did the post-production work on The Golden Compass, winning Oscar and BAFTA awards for its trouble. The armoured polar bear it animated for that movie had 200 million individual hairs which moved as the bear moved. Rendering it needed a lot of kit.

Framestore is the largest visual effects and computer animation studio in Europe. It has more than 20 years of experience in digital film and video technology, and employs 800 or so staff out of three buildings in Soho, with another office based in New York.

Despereaux publicity image

The Tale of Despereaux: How many hairs under that hat?

The company has just finished a two-year project rendering the Universal Studios cartoon feature The Tale of Despereaux, and that needed probably the largest CGI rendering supercomputer in Europe to do the job. The voice cast includes Dustin Hoffman, Kevin Kline, Sigourney Weaver and Robbie Coltrane. The movie is an animation of the 2003 fantasy book of the same name by Kate DiCamillo and it's about a cute mouse, Despereaux Tilling, who has exceptionally large ears. A rat named Roscuro, voiced by Dustin Hoffman, is the villain.

The Despereaux project wasn't quite as hairy as The Golden Compass though, as there were only 413,138 hairs on the rodent's head.

The work was complicated because the Framestore creatives had been briefed to create a 'look' for the full-length cartoon based on the Dutch Masters with relatively soft lighting and detailed shadows. There was a fixed deadline, meaning animation proceeded in parallel with the development of the processing needed to render the Vermeer-esque final look.

This parallel approach increased render farm and storage demands, because many intermediate stages of production data had to be retained to avoid unnecessary animation rework whilst the fine tuning of the lighting effects and colour was worked on. There were several specialist teams working in parallel with the rendering, the lighting work being concentrated more towards the end of the project.

The renderfarm supercomputer used 1,000 clustered vanilla Dell X86 servers linked by 4Gbit/s Fibre Channel to an initial 50TB of RAID-6-protected storage, front-ended with HP storage server processors, using Infortrend arrays. A Linux cluster file system was implemented and each Dell server core had 2GB of DRAM. The storage ultimately grew to 200TB.

Why Dell CPUs for the render farm? Framestore's technology director Steve Prescott said: "They're the people who can react the quickest. We ordered 1,000 cores and they delivered it five days later. HP just can't react as quickly."

The Lustre cluster

Apart from the 6,000 core render farm, using Dell dual-socket, quad core Xeons, there is a Lustre cluster file system meta-server with two 4Gbit/s Fibre Channel-attached RAID arrays, using SAS drives for speed. There are also eight object storage servers using HP processors which control the bulk storage, with each having 24 Infortrend EonStor arrays, attached via dual 4Gbit/s FC links, and populated with SATA drives, not faster SAS ones. Prescott said: "We got the aggregate bandwidth we needed because we had so many spindles."

Why use Infortrend arrays? Why not storage from HP or IBM or EMC or NetApp, well-known for RAID 6, arrays? Prescott said Framestore had used Infortrend products for the last ten years. "We were confident we could trust them [and] Infortrend is very good value."

Prescott's people wanted a system they could get up and running quickly. Infortrend's arrays were a known quantity and RAID 6 provided the extra protection needed in a large array.

Despereaux scene

Prescott also wanted a system that could grow as the data amounts grew: "At peak working we were generating 5TB per night, so reliable high performance storage was central to our system design... 80 per cent of the rendering for the film was completed in the last three months of production. We designed the systems to scale. The project started with 50TB of storage which we grew by an additional 150TB as we worked."

The Render software is Pixar's Renderman, which Prescott says is a de facto standard.

At the peak of production there was a crew of 278 Framestore people using 4,700 of the 6,000 cores for work on The Tale of Despereaux, with other projects running in parallel. There are 40,089 individual assets in the film; 25 hero characters in 60 hero environments were modelled, surfaced and textured, as well as 12 secondary characters.

The Framestore crew generated 90 million files. To safeguard these, Framestore mirrored and snapshot the primary storage, installing its own dark fibre 10Gbit/s network between its three Soho production offices and a London Docklands data centre. All the project data was replicated and backed up across multiple locations each day.

The biggest output delivery in one week was 335 shots, and 1,200 shots were delivered during the last month of production as the processing load built up.

Prescott thinks that Framestore has built the most powerful CGI render farm in Europe. It used to be that Formula 1 Grand Prix was the place where IT suppliers established bragging rights. CGI render farms have become the preferred place these days because the work obviously stretches servers, networking, storage and file systems and because we know that the customers have bought the kit instead of agreeing some kind of sponsorship display aspect to the supply deal.

Framestore found that, all in all, the Despereaux project was larger then The Golden Compass, even though the Despereaux character had fewer hairs than the armoured polar bear in the Compass movie.

The Tale of Despereaux is showing in UK cinemas now, if you fancy taking your kids to see the end result of some serious CGI toil. ®