forked from TrueCloudLab/restic
189e0fe5a9
Hard links to the same file now get the same inode within the FUSE
mount. Also, inode generation is faster and, more importantly, no longer
allocates.
Benchmarked on Linux/amd64. Old means the benchmark with
sink = fs.GenerateDynamicInode(1, sub.node.Name)
instead of calling inodeFromNode. Results:
name old time/op new time/op delta
Inode/no_hard_links-8 137ns ± 4% 34ns ± 1% -75.20% (p=0.000 n=10+10)
Inode/hard_link-8 33.6ns ± 1% 9.5ns ± 0% -71.82% (p=0.000 n=9+8)
name old alloc/op new alloc/op delta
Inode/no_hard_links-8 48.0B ± 0% 0.0B -100.00% (p=0.000 n=10+10)
Inode/hard_link-8 0.00B 0.00B ~ (all equal)
name old allocs/op new allocs/op delta
Inode/no_hard_links-8 1.00 ± 0% 0.00 -100.00% (p=0.000 n=10+10)
Inode/hard_link-8 0.00 0.00 ~ (all equal)
44 lines
1.2 KiB
Go
44 lines
1.2 KiB
Go
//go:build darwin || freebsd || linux
|
|
// +build darwin freebsd linux
|
|
|
|
package fuse
|
|
|
|
import (
|
|
"encoding/binary"
|
|
|
|
"github.com/cespare/xxhash/v2"
|
|
"github.com/restic/restic/internal/restic"
|
|
)
|
|
|
|
// inodeFromName generates an inode number for a file in a meta dir.
|
|
func inodeFromName(parent uint64, name string) uint64 {
|
|
inode := parent ^ xxhash.Sum64String(cleanupNodeName(name))
|
|
|
|
// Inode 0 is invalid and 1 is the root. Remap those.
|
|
if inode < 2 {
|
|
inode += 2
|
|
}
|
|
return inode
|
|
}
|
|
|
|
// inodeFromNode generates an inode number for a file within a snapshot.
|
|
func inodeFromNode(parent uint64, node *restic.Node) (inode uint64) {
|
|
if node.Links > 1 && node.Type != "dir" {
|
|
// If node has hard links, give them all the same inode,
|
|
// irrespective of the parent.
|
|
var buf [16]byte
|
|
binary.LittleEndian.PutUint64(buf[:8], node.DeviceID)
|
|
binary.LittleEndian.PutUint64(buf[8:], node.Inode)
|
|
inode = xxhash.Sum64(buf[:])
|
|
} else {
|
|
// Else, use the name and the parent inode.
|
|
// node.{DeviceID,Inode} may not even be reliable.
|
|
inode = parent ^ xxhash.Sum64String(cleanupNodeName(node.Name))
|
|
}
|
|
|
|
// Inode 0 is invalid and 1 is the root. Remap those.
|
|
if inode < 2 {
|
|
inode += 2
|
|
}
|
|
return inode
|
|
}
|