Anyone remember PFSCK, aka parallel fsck that fired up multiple parallel fsck instances, one per filesystem and used bidirectional pipes to pass commands from the operator to each individual fsck stream. Cut boot times down quite a bit on healthy systems.

I believe the filesystem MOUNT table file on ROOT had fields related to controlling PFSCK behavior

I remember hacking it for some reason related to performance, But GOK why......

On Mon, Mar 6, 2023, 3:59 AM Jonathan Gray <jsg@jsg.id.au> wrote:

On Mon, Mar 06, 2023 at 03:14:27AM -0500, Noel Chiappa wrote:
>
> I've also been amusing myself trying to figure out who wrote:
>
> http://ana-3.lcs.mit.edu/~jnc/tech/unix/s1/fcheck.c

According to Guy Harris in
https://groups.google.com/g/net.unix/c/-H9x36DMOBQ/m/4mcL76lKbmMJ

'they had to replace "icheck" and "dcheck" with a new program which
would do most of the dirty work of file system repair for them -
Hal wrote one called "fcheck", which cleaned V6 file systems, and
which appeared in source-code form on the PWB/UNIX 1.0 distribution
tape. Unfortunately, PWB/UNIX 1.0 modified the V6 file system so
that it didn't support "huge" files, and the eighth indirect pointer
pointed directly to a block as the other seven did, so the "fcheck"
there wouldn't fix a vanilla PWB/UNIX file system, but it worked
just fine on a vanilla V6 FS.'