CAMPBELL, USA: Altos Design Automation Inc. announced new versions of its industry-leading IP characterization products, Liberate and Variety, that improve throughput by a factor of 2-3X. The new 3.1 version employs a distributed processing "packet" technology that packages cell characterization simulations together and submits them to a job-distribution queue as a single process.
By optimizing the size of these cell packets, job queuing overhead is greatly reduced, optimizing the use of multi-CPU cores that use shared memory. Throughput is further improved by enabling multi-threading for the simulations within each packet, conserving both memory and CPU resources for each machine.
Multiple distinct packets utilize all available memory and CPU threads simultaneously, resulting in a highly efficient usage of compute resources and providing up to 3X improvement in throughput. The new packet method is particularly well-suited to the large cell libraries used by leading IP providers, foundries and semi-conductor firms that may contain as many as 6,000 cells.
"Previously distributed modes for cell characterization were either at the library or cell level. As library sizes have increased, library-level distribution has become too large, while cell-level distribution is too small for all but the largest cells due to the job queue overhead", said Altos CTO and founder, Ken Tseng.
"By creating an intermediate layer of granularity or "packet" we have optimized the library characterization problem to best suit today's compute farm environments that typically comprise hundreds of multi-CPU machines managed by a job queuing system. We have also been able to parallelize much of the sequential processing that is performed prior to simulation such as automatic vector generation, so that each "packet" is an autonomous process with a small memory footprint.
"One of our leading foundry customers has reported 2.5X improvement in turnaround time on a commercial library of ~1,500 cells while another of our leading fab-less customers has reported >3X improvement for a 4,000 cell library."
Altos' CEO and founder, Jim McCanny, added: "Altos is continuing to raise the bar in optimizing characterization performance. In addition to improved turn around time, the 3.1 release adds support for additional third party simulators, improves IBIS support for complex I/O cells such as DDR2 and DDR3 that feature on-die termination (ODT), and offers the ability to use distinct process models for leakage characterization."