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Hello,
On Thu, 25 Jan 2001, Tyrel Beede wrote:
> Just a thought,
>
> Concerning a fastest response class scheduling algorithm which would
> function to balance response time through out the cluster by manipulating the
> number and type of connection to each node of the cluster, is and how would it
> be possible to develop an algorithm that works by evaluating the rate of
> change
> for the sum of the client tcp windows? My knowledge is not exact but would it
> be possible to this? Realistically how fast does the environment between a
> client and server on the internet change? Assuming a tcp protocol like ftp
> which for now we assume is primarily performing bulk data transactions and
> thus
> over a significant period of time it would act to continuously fill up the
> window size. Therefor this would result in a number of connections to a
> single
Only for NAT or for any forwarding method when the client uploads
data.
> node having filled windows or filling windows most of the time. Now the rate
> at
> which the windows are/or become filled would be dependent on three factors:
> the
> size of the physical links over the length of the connection, the current
> congestion over those links, and also the current congestion at the end server
> node(the node's ability to process data). Now if the sum of the rate of
> change
> of these links is averaged a load value may be calculated for each node and
> as a
> result connections maybe intelligently balanced. This should also apply to
> data
> exchange types which do not resemble bulk ftp. I also wonder if it would be
> possible to create a framework within the lvs to enable balancing at a packet
> granularity rather than at a connection granularity? Would it be possible for
Are you trying to balance a ftp traffic?
Hm, what do you mean: balancing at a packet/connection
granularity. I don't understand. Scheduling of independent packets?
What service needs this?
> the lvs to record the necessary state information to manipulate acks in such a
> manner that it could pass off connections between identical servers while the
> connection always appeared to be "up" to the client? Seems like all this
> would
> require lots of packet mugging so yeah...
You have a very strange vision for the load. Be more specific.
Explain carefully each idea you mention in this mail, I hear your
bullets but can't see them :)
IMHO, the director needs information from the real servers to
balance the load. There are many parameters we can monitor and we can
make different expressions based on these parameters: packet rate,
cpu usage, free memory. In this way, we can select different expressions
for the different services. There is a reason for this: each service
loads differently the real host or may be other hosts too, for example
databases, etc.
I don't believe in your theory about the fastest response
schedulng but you can surprise us with more specific details and
may be results :) Is this scheduler for NAT only?
> Thanks, Tyrel
Regards
--
Julian Anastasov <ja@xxxxxx>
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