As serde_json will otherwise read files 1 byte at a time.
Writing is a bit better, but syntacitcal elements (quotes, braces,
commas) still often show up as single write syscalls, so use BufWriter
there as well.
Note that while we do store the file in the resulting objects, we do not
need to keep the buffered read/writers as we always `seek` to the
beginning on further file operations.
Reported-by: Mark Schouten <mark@tuxis.nl>
Link: https://lists.proxmox.com/pipermail/pbs-devel/2022-April/004909.html
Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
b300e6fbc2