...distributed

For loosely coupled systems. Tightly coupled systems, such as those sharing a clock and memory between CPUs, are outside the scope of this thesis.

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...architectures

MPP, SIMD, dataflow etc.

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...local

RPC when the client and server coexist on the same host.

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...uncharacterisable

A batch process that will with probability P sort a 10 element file and with a probability of (1-P) sort a 100000000 element file is difficult to characterise, and the actual behaviour can only be determined at runtime.

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...scheduling

Where there is workload that is not scheduled, or scheduled by independent agents.

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...balance

Balancing within clusters and amongst the clusters in a hierarchical fashion is a partial solution.

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...load

Foreign load is load that is offloaded by other hosts onto the host.

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...demands

Satisfies dynamic process behaviour - at stage 1 a process may require X and then later Y, if X and Y are best provided for from different hosts, then the best solution may be to move the process during execution to suit the different phases of execution.

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...rare

Between 8 and 10 processes out of 8.5 million are both CPU and IO bound.

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...hosts

This also solves the situation where processes are nonhomogeneous in behaviour (i.e., those whose resource requirements change over its execution).

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...k-means

34#34, where 35#35, 36#36 is the 37#37 cluster of k and 38#38 is the centroid of 36#36.

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...heterogeneous

Heterogeneous in both capability and compatibility.

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...stdin

Stdin and stdout are UNIX files intended for writing to and from the console.

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...heterogeneous

Heterogeneous in capability rather than compatibility

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...actions

Self assignment is not a permissible action, and therefore the set of actions does not include an assignment to the local host.

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...cs

These names are the compute server and remote server. They are in this form to maintain consistency with the conventions adopted in chapter 8.

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...(Adaline

Developed by Widrow and Hoff, 1960.

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...servers

As this chapter deals with a simulation based on a real system, the generic term `host' is replaced with the more accurate and specific term `compute server'.

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...events

User interactions and timer events. This is discussed in section 6.2.8.

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...used

CPU user time is the time spent executing user level code, while system time is the time spent executing kernel code. This user time should not be confused with the time spent interacting with a user.

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...blocks

The only information is the number of bytes, the use of 64 byte blocks in the accounting log has nothing to do with the size or frequency of transfers.

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...chunk

A CPU chunk is the defined in section 6.3.1

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...

Vmstat reports amongst other things, the activity of the virtual memory system.

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...

A UNIX utility for displaying the previously executed commands from the accounting logs

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...time

That is, the time the process would take if it were a batch process.

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...Figure 105#105f

Approximated with 106#106, where A = 12000 and B = 6

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...

Iostat is a UNIX command that reports the disk activity.

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...all

To ensure fairness in the evaluation of the load distribution policies, all must have access to the same information on which to distribute the workload.

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...components

This is in effect a linear combination which was found to give good performance by Ferrari and Zhou [FZ87].

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...respond

If complete information is required. If only the first one or few replies are needed this is less of a problem.

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...placements

Process migration does not suffer from this problem as it is initiated immediately after the load update, and therefore the load data is used before it becomes stale.

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...rsh

Rsh is a Unix command for remote execution.

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...thumb

These rules of thumb have the interesting implication that the mean of the distribution is infinite.

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...loaded

Encloses less area, denoted with the dashed lines

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...187#187

Algorithm terms are defined on page 

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...168

Traces for the entire month of May 1995 were recorded, however the most interesting part of the trace was the last week of term. Thus all samples are drawn from this period, giving a total of 168 one hour periods.

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...time

The response time of a process is the total time it spent in the system, from initiation to termination.

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...

Defined on page 

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...Time:

From now on batch job response time will be abbreviated to response time.

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...mechanism

Defined in section 7.4 page 

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