12 May
2015
12 May
'15
10:39 a.m.
On May 12, 2015, at 1:28 PM, Holm Tiffe <holm at
freibergnet.de> wrote:
Johnny the success proves that I'm right. After "erasing" the disk the
exerciser run found no soft read errors anymore. "Soft error read count 0".
BTW: This was the disk that I've hammered :-)
Servo data is unaffected by formatting. If you have read errors, simply overwriting the
drive may be sufficient, but certainly formatting would. That assumes such an operation
even exists; in some cases, when people say ?format? they simply mean pattern-checking the
drive and/or creating a new empty file system on it. For example, in PDP-11 disks, a
?real? format operation that does more than just rewrite the data appears only on a few
drive models: RP03 and RK05 do, most others don?t. Some MSCP drives also, I think, but
those only via magic code running on the controller, not from the OS.
On drives with dedicated servo tracks (RP04 family for example) the servo head is only a
read head. But in all cases, servo writing is done on specialized machines, and only at
the factory.
paul
...
The exerciser showed some correctable soft errors, wich is pretty much
normal I think. Reformating the drive should simply "freshen up" the data
tracks but erase should do the same in this regard.
Since the distks aren't containing anything interresting, it would be the
right time now to do a reformat.
I think the head assembly has an voice coil engine anyways, so servo tracks
are needed to do the positioning. It is clear that they aren't affected from
a reformat...