| author |  Ryan Liptak <squeek502@hotmail.com> 2023-06-07 22:37:53-07:00 |
| committer | Ryan Liptak <squeek502@hotmail.com> 2023-06-08 02:16:15-07:00 |
| log | 2f188290e203780752597b0263581590af3a69b2 |
| tree | ebab0d11aa6a249ef05337725f57d868e848a75c |
| parent | 00ff65357666a7ec161d6e80c92be2ccc79e3638 |
Use `iterateAssumeFirstIteration` in `Walker.next` to avoid unnecessary lseek calls
Since we are opening each directory for iteration, we know that we don't need to reset the cursor's directory before iterating. Using `iterateAssumeFirstIteration` skips the cursor resetting which eliminates an `lseek` syscall for every directory opened on non-Windows platforms.
This doesn't seem to actually matter much for performance (1.01 ± 0.02 times faster when walking /home/ on my system) but avoiding unnecessary syscalls is always nice anyway.1 files changed, 1 insertions(+), 1 deletions(-)
lib- std
lib/std/fs.zig+1-1
| ... | ... | @@ -972,7 +972,7 @@ pub const IterableDir = struct { |
| 972 | 972 | { |
| 973 | 973 | errdefer new_dir.close(); |
| 974 | 974 | try self.stack.append(StackItem{ |
| 975 | .iter = new_dir.iterate(), | |
| 975 | .iter = new_dir.iterateAssumeFirstIteration(), | |
| 976 | 976 | .dirname_len = self.name_buffer.items.len, |
| 977 | 977 | }); |
| 978 | 978 | top = &self.stack.items[self.stack.items.len - 1]; |