load balancing question
John E. Malmberg
wb8tyw at qsl.net
Sun Oct 6 03:25:59 GMT 2002
Stephan Stapel wrote:
> Dear people on the list!
> I hope it's ok to ask a feature question on this core-feature list.
> What I would like to know is whether there are some efforts on
> implementing load balancing features into samba or some experiences/
> experiments in this area. As standard-Windows doesn't offer these
> features, adding them would give samba-based systems yet another
> (very big) advantage over a standard nt server system. Just that you
> know why I'm asking for this. We have the problem to serve 3d scenes
> as well as image data to about 100 render nodes running under Windows
> NT. When starting to render, all machines are asking at exactly the
> same time for exactly the same data, which might be about 500
> megabytes per machine. Action like this results into a server load of
> about 30-50 which isn't really satisfactory...
Load balancing can be implemented with out making any changes to Samba,
and has been.
Load balancing on TCP/IP generally requires having a "metric" server on
each host that feeds information to a DNS that understands how to round
robin connection requests.
The next issue that you run into is simultaneous access to the disks.
Since this is read only data, you could replicate it before the
rendering, but I am guessing that there is some reason that you are not
replicating the data.
If your platform allows simultaneous access to disks, then the load
broker should be sufficient.
If not, then you need to do more research. If you do not have multiple
hosts sharing simulaneous access to the disks, then there probably is
not much to gain by load sharing them from multiple servers, as only one
host will really be doing all of the work.
But again, there is nothing in Samba that prevents using existing load
sharing techniques, if the underlying platform supports it.
Now a server load of 30-50 to a machine is not excessive to some classes
of machines, and if they are really all hitting the same data, then file
system caching will help. Many of the systems my employer sells can
handle that type of load easily, they also support simultaneous disk
access from multiple hosts.
What actually would help more is a custom protocol that used multicast
packets which would reduce the total amount of network traffic.
wb8tyw at qsl.network
Personal Opinion Only
More information about the samba-technical