Sector size of 4096 bytes (not 512)

Dag-Erling Smørgrav des at des.no
Tue Aug 26 14:05:20 UTC 2008


Dag-Erling Smørgrav <des at des.no> writes:
> Doesn't newfs figure this out on its own, based on the parameters
> reported by ata / cam?

It does, actually:

        if (sectorsize == 0)
                if (ioctl(disk.d_fd, DIOCGSECTORSIZE, &sectorsize) == -1)
                        sectorsize = 0; /* back out on error for safety */
        /* ... */
        if (fsize <= 0)
                fsize = MAX(DFL_FRAGSIZE, sectorsize);
        if (bsize <= 0)
                bsize = MIN(DFL_BLKSIZE, 8 * fsize);

If I read the sysinstall code correctly, it won't specify a block and
fragment size unless you actually press 'N' to set custom options - at
which point it will initialize them to "-b 16384 -f 2048" (which are the
newfs defaults for disks with sector sizes <= 2048) before displaying
the dialog box where you can edit them.

DES
-- 
Dag-Erling Smørgrav - des at des.no


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