gvisor-performance

Use when modifying gVisor in ways with potential performance implications; as a kernel, gVisor's performance matters almost as much as its security. Load imperatively when editing this performance-sensitive code: * Syscall hot path: `pkg/sentry/kernel` (`task_run.go`, `task_syscall.go`), `pkg/sentry/syscalls/linux`, and app-memory copy layers (`pkg/usermem`, `pkg/safemem`, `pkg/safecopy`, `pkg/marshal`). * Platform: `pkg/sentry/platform`, `pkg/ring0`. * Sandbox startup: `runsc/boot`, `runsc/container`, `runsc/sandbox`. * Serialization and checkpoint/restore: `pkg/state`, `pkg/sentry/state`. * Netstack: `pkg/tcpip`. * File I/O: `pkg/sentry/vfs`, `pkg/sentry/fsimpl`. * Memory management: `pkg/sentry/mm`, `pkg/sentry/pgalloc`. * Gofer IPC: `pkg/lisafs`, `runsc/fsgofer`. * Go `init()` functions, which run on every binary startup. Also load for any change with potential performance impact, even outside these paths.