On Thu, Nov 04, 2021 at 02:24:26PM -0700, Junio C Hamano wrote:
> Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> writes:
>
> > I think it would probably be best to create a git_fsync_fd() function
> > which is non-fatal and has that config/while loop, and have
> > fsync_or_die() be a "..or die()" wrapper around that, then you could
> > call that git_fsync_fd() here.
>
> Adding git_fsync_fd() smells like a poor taste, as git_fsync() takes
> an fd already. How about making the current one into a static helper
>
> -int git_fsync(int fd, enum fsync_action action)
> +static int git_fsync_once(int fd, enum fsync_action action)
> ...
>
> and then hide the looping behavior behind git_fsync() proper?
>
> int git_fsync(int fd, enum fsync_action action)
> {
> while (git_fsync_once(fd, action) < 0)
> if (errno != EINTR)
> return -1;
> return 0;
> }
>
> fsync_or_die() can be simplified by getting rid of its loop.
>
> None of that needs to block Patrick's work, I think. A version that
> uses raw fsync() and punts on EINTR can graduate first, which makes
> the situation better than the status quo, and all the ongoing work
> that deal with fsync can be extended with an eye to make it also
> usable to replace the fsync() call Patrick's fix adds.
Is there some reason we shouldn't die if writing the ref fails? We are
already accustomed to dying if fsyncing a packfile or the index fails.
I assume the number of refs updated is not that high on any given git
operation, so it's not worth having a batch mode for this eventually.
Thanks,
Neeraj
