[tahoe-dev] tree thawed for post-1.8.2 development

[Jan-Benedict Glaw]

On Mon, 2011-01-31 22:32:48 -0800, Brian Warner <warner at lothar.com> wrote:
>  * fixes to upload-happiness

I once saw an email (or an ticket entry) addressing share balancing.
If I remember correctly, the author suggested to spread shares by
giving each node a number of key/value pairs and spreading the shares
so that the number of two nodes having a common value for any key is
minimal. That bad description may be supplied by an example:


# Node 1
datacenter=1
rack=17
HE=1
power_supply_chain=2

# Node 2
datacenter=1
rack=17
HE=3
power_supply_chain=2

# Node 3
datacenter=1
rack=17
HE=2
power_supply_chain=1


In this example, the first two nodes share a common UPS, while node 3
is on a different one. (Other than that, they're in the same rack in
the same datacenter.)  In this example, if you had to distribute two
shares, these should go to (node 1 or node 2) and node 3, but not to
node 1 and node 2, because they share three common tag/values, while
the other combination only shares two with the others.

As said, that was another person's idea, but I cannot find a
reference. Though it would be nice to implement, because users would
gain more control over share distribution. (Would even be nice for
running multiple nodes on one machine with several filesystems.)

MfG, JBG

-- 
      Jan-Benedict Glaw      jbglaw at lug-owl.de              +49-172-7608481
Signature of:           Ich hatte in letzter Zeit ein bißchen viel Realitycheck.
the second  :               Langsam möchte ich mal wieder weiterträumen können.
                             -- Maximilian Wilhelm (18. Mai 2005, #lug-owl.de)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 197 bytes
Desc: Digital signature
URL: <http://tahoe-lafs.org/pipermail/tahoe-dev/attachments/20110201/41bba971/attachment.pgp>