mirror of
https://github.com/seaweedfs/seaweedfs.git
synced 2026-10-27 15:30:45 +01:00
Chris Lu
1996c6aec6
* volume server: open volume files with O_NOATIME Nothing reads the atime of .dat, .idx, .sdx, or EC files, but every needle read still dirtied the inode: even relatime writes atime on the first read after each write, so an actively written volume paid a metadata write per read/write cycle, and strictatime mounts paid one per read. Open the serving handles with O_NOATIME, falling back to a plain open when the file belongs to another owner (EPERM). Claude-Session: https://claude.ai/code/session_015uVY4diBgEn3VYQoc2eMuD * seaweed-volume: mirror the O_NOATIME volume file opens Same change as the Go volume server: serving handles for .dat, .idx, .sdx, .ecx, .ecj, and shard files open with O_NOATIME on Linux, with a plain-open fallback on EPERM. Claude-Session: https://claude.ai/code/session_015uVY4diBgEn3VYQoc2eMuD * route the tier-down and recreate .dat opens through the no-atime helper Review caught the Rust tier-down swap opening the local .dat directly. The Go swapToLocalDatBackend and the zero-length read-only .dat recreate in maybeWriteSuperBlock had the same gap: all three install long-lived serving handles. Claude-Session: https://claude.ai/code/session_015uVY4diBgEn3VYQoc2eMuD
28 lines
1.0 KiB
Rust
28 lines
1.0 KiB
Rust
//! Opening volume data and index files without access-time updates.
|
|
|
|
use std::fs::{File, OpenOptions};
|
|
use std::io;
|
|
use std::path::Path;
|
|
|
|
/// Open a volume data or index file with `O_NOATIME`. Nothing reads these
|
|
/// files' atime, but without the flag every needle read dirties the inode —
|
|
/// even relatime writes atime on the first read after each write, so an
|
|
/// actively written volume pays a metadata write per read/write cycle.
|
|
/// Matches Go's `backend.OpenVolumeFile`.
|
|
pub fn open_volume_file(opts: &OpenOptions, path: impl AsRef<Path>) -> io::Result<File> {
|
|
let path = path.as_ref();
|
|
#[cfg(target_os = "linux")]
|
|
{
|
|
use std::os::unix::fs::OpenOptionsExt;
|
|
let mut noatime = opts.clone();
|
|
noatime.custom_flags(libc::O_NOATIME);
|
|
match noatime.open(path) {
|
|
// O_NOATIME is refused unless we own the file or hold CAP_FOWNER.
|
|
Err(e) if e.raw_os_error() == Some(libc::EPERM) => opts.open(path),
|
|
result => result,
|
|
}
|
|
}
|
|
#[cfg(not(target_os = "linux"))]
|
|
opts.open(path)
|
|
}
|