Commit graph

4 commits

Author SHA1 Message Date
greatroar
5d4568d393 Write sparse files in restorer
This writes files by using (*os.File).Truncate, which resolves to the
truncate system call on Unix.

Compared to the naive loop,

	for _, b := range p {
		if b != 0 {
			return false
		}
	}

the optimized allZero is about 10× faster:

name       old time/op    new time/op     delta
AllZero-8    1.09ms ± 1%     0.09ms ± 1%    -92.10%  (p=0.000 n=10+10)

name       old speed      new speed       delta
AllZero-8  3.84GB/s ± 1%  48.59GB/s ± 1%  +1166.51%  (p=0.000 n=10+10)
2022-09-24 21:18:48 +02:00
Michael Eischer
c60540b196 add go:build headers everywhere 2022-03-28 22:23:47 +02:00
Michael Eischer
603bb0e309 restore: Use proper context while loading snapshot 2020-10-09 22:37:56 +02:00
Igor Fedorenko
bda8d7722e restorer: Optimize empty file restore
don't create fileInfo structs for empty files. this saves memory.
this also avoids extra serial scan of all fileInfo, which should
make restore faster and more consistent.

Signed-off-by: Igor Fedorenko <igor@ifedorenko.com>
2018-10-14 17:39:42 +02:00