Transparent, incremental checkpointing at kernel level: A foundation for fault tolerance for parallel computers

We describe the software architecture, technical fea-tures, and performance of TICK (Transparent Incre-mental Checkpointer at Kernel level), a system-level checkpointer implemented as a kernel thread, specifi-cally designed to provide fault tolerance in Linux clus-ters. This implementation, based on the 2.6.11 Linux kernel, provides the essential functionality for trans-parent, highly responsive, and efficient fault tolerance based on full or incremental checkpointing at system level. TICK is completely user-transparent and does not require any changes to user code or system li-braries; it is highly responsive: an interrupt, such as a timer interrupt, can trigger a checkpoint in as little as 2.5µs; and it supports incremental and full check-points with minimal overhead—less than 6 % with full checkpointing to disk performed as frequently as once per minute.