[9fans] adm. pseudo-WORM fs

[9fans] adm. pseudo-WORM fs

[forsyth]

>>Who uses pseudo-WORM jukebox?
>>How do you back up the pseudo-WORM, just use scuzz to 8mm tape?

i use a pseudo-worm (on a 4Gb IBM drive).  9fs dump is well worthwhile.
backup is done in an `allow' mode to other media
via disk/mkfs -a at the moment.

one problem is that i believe it is not straightforward
as things stand to extend a pseudo-worm.
you need to dump/reinit/restore when it fills up (losing the history).
that's what i did when i ran one at the university on a much smaller disc.
(i later switched to using a plain file system without a dump file system.)

fortunately, my current pseudo-worm is big enough that it's not a problem just
yet.

i'd quite like, however, to switch to a proper jukebox of some sort.
i'm curious what changes were required to support the HP ones,
and what other decent ones might be on the market.

[9fans] adm. pseudo-WORM fs

[jim]

	>i'd quite like, however, to switch to a proper jukebox of some sort.
	>i'm curious what changes were required to support the HP ones,
	>and what other decent ones might be on the market.

at the time we changed to the hp jukebox some other changes were made
(e.g. more parallelism, multiple network interfaces) but the changes for
the jukebox itself were fairly minor, implementing the standard scsi
medium-changer commands. it has worked so far on both brands of jukebox
we've tried, hp and a much smaller r/w one which i can't remember the
name of.

--jim

[9fans] adm. pseudo-WORM fs

[Kazumi]

WORM related questions...

Who uses WORM jukebox __outside__ of bell-labs?
Which model of WORM jukebox, Sony or anything else?
Both good/bad experiences with WORM jukebox are welcome.

Who uses pseudo-WORM jukebox?
How do you back up the pseudo-WORM, just use scuzz to 8mm tape?

[9fans] adm. pseudo-WORM fs

[Kenji]

Hello 9fans!

I have installed pseudo-WORM file system.
However I don't know how to administrate the system.
My system is:
	w0: 4.3GB
	w1: 500MB
	w2: 500MB
and the configuration is:
	filsys main c[w1w2]fw0

I want to know how much the pseudo-WORM is consumed.

Statw command on 9fs shows:
9fs% statw
cwstats
	nio	=	0	0	0
	cache main
		maddr	=	           3
		msize	=	    5107
		caddr	=	      514
		csize		=	255350
		sbaddr	=	239333
		craddr	=	374767	374767
		roaddr	=	374772	374772	0+68%
		slast		=			103908
		snext	=			374771
		wmax	=	374770			0+68%
		wsize	=     1058376			1+93%
		57161	none
		       55	dirty
			0	dump
	       198075	read
		       59	write
			0	dump1
		cache	2% full

Thanks,

Kenji Arisawa
E-mail: arisawa@aichi-u.ac.jp