[RC5] Wheres the blocks?

rc5 at xfiles.nildram.co.uk rc5 at xfiles.nildram.co.uk
Sun Jan 10 22:19:59 EST 1999

On Sat, 9 Jan 1999, Robert A. Rosenberg wrote:
> At 15:21 -0500 on 01/09/99, John Campbell wrote about Re: [RC5] 
> Wheres the blocks?:
> > 	The problem is that there's no real way to tell whether a block
> > that's been assigned is lost or just waiting on a slow machine. The solution
> > is to keep buffer sizes small and, for the slower machines, go after the
> > smallest blocks you can get, to keep the latency times of your blocks as low
> > as you can get it so the keyserver doesn't reassign the blocks you've
> done/are doing.
> It would also help if there was an option to Flush (ie: Return for 
> recycling) buffers in the IN buffer. Once a block has been assigned, 
> it is "Lost" until you  loop around and recycle it or the "owner" 
> sends it back marked "Checked." If someone wants to shut a machine 
> down, why not let him return the unchecked blocks and let others get 
> a crack at it (he can refresh the IN buffer when he next connects).

Actually, I think that would be a great idea - I think GIMP allows
you to do something similar... You should be able to 'Return' blocks.

Or even better - the client should automatically Return blocks over
a certain (settable, either by user or proxy) age.. So for RC5 you
could return blocks over 1 month old, and for DES you could return
any blocks you still have over 12 hours old (obviously it only
does this on scheduled connects).
> This also keys into a BUG/DESIGN Flaw that I've found. When I stop 
> the process, the current block gets returned to the IN Buffer marked 
> x% done and when I start up it gets selected and resumes where I left 
> off. If, OTOH, my Client crashes, there is no record that I was 
> working on the block and when I restart, the block is no longer in 
> the IN Buffer and the number of blocks is now reduced by 1. Thus the 
> Block in Process at the Crash is LOST and must wait to be reassigned. 
> I think the client should log the block back to the IN Buffer in 
> "Stopped" state with the % Done (just as it does when I REALLY shut 
> down) every time it updates the Status Display. Thus ALL restarts 
> after a crash will resume just as if there were a normal shutdown.

Use checkpoint files.

Then your current block will be saved every 5 minutes or so.
David Taylor
dtaylor at xfiles.nildram.co.uk.spam

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