Fast and effective memory management is crucial for many applications, including web servers, database managers, and scientific codes. However, current memory managers do not provide adequate support for these applications on modern architectures, severely limiting their performance, scalability, and robustness. In this talk, I describe how to design memory managers that support high-performance applications. I first address the software engineering challenges of building efficient memory managers. I then show how current general-purpose memory managers do not scale on multiprocessors, cause false sharing of heap objects, and systematically leak memory. I describe a fast, provably scalable general-purpose memory manager called Hoard (available at www.hoard.org) that solves these problems, improving performance by up to a factor of 60.

1. Hoard: A Scalable Memory Allocator for Multithreaded Applications Emery Berger , Kathryn McKinley * , Robert Blumofe, Paul Wilson Department of Computer Sciences * Department of Computer Science

11. So What Do We Do Now?

16. Performance: threadtest speedup (x,P) = runtime (Solaris allocator, one processor) / runtime (x on P processors)

17. Performance: Larson Server-style benchmark with sharing

18. Performance: false sharing Each thread reads & writes heap data