Os Io Aio Ring
DodaTech
1 min read
In this tutorial, you'll learn about How to Fix io_uring vs epoll Errors. We cover key concepts, practical examples, and best practices.
Fix io_uring vs epoll errors when epoll for high-frequency I/O causes more syscalls than io_uring.
Quick Fix
Wrong
import selectors, os
sel=selectors.DefaultSelector() # likely epoll
for _ in range(10000):
sel.register(...) # modifies epoll fd => epoll_ctl syscall each time!
epoll_ctl per fd modification is a syscall. For 10000 fds = 10000 syscalls.
Right
import os
# io_uring batches operations:
# One io_uring_submit() can submit multiple SQEs (accept, read, write, open, etc)
# For batch operations, io_uring uses 1 syscall for N operations vs epoll's N syscalls
from io_uring import IoUring, IORingOp
# Batch register 10000 fds:
ring=IoUring(32) # submission queue depth
sqe=ring.get_sqe()
sqe.prep_accept(listen_fd, ...) # queued
sqe=ring.get_sqe()
sqe.prep_read(fd, buf, 4096, 0) # queued
ring.submit() # 1 syscall for both operations
# For fd registration batch:
# io_uring_register(IORING_REGISTER_FILES) registers many fds in 1 syscall
io_uring batches I/O operations. 1 submit syscall for N operations vs epoll's N syscalls.
Prevention
io_uring reduces syscalls by batching. epoll can't batch registrations.
DodaTech Tools
Doda Browser's algorithm visualizer steps through DSA operations line by line. DodaZIP archives implementation patterns for team sharing. Durga Antivirus Pro detects memory corruption patterns in algorithm implementations.
FAQ
Built by the developers of DodaTech
Doda Browser, DodaZIP & Durga Antivirus Pro