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@@ -403,28 +403,30 @@ is based on multiple linear regression. In this model, the user
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defines both the relevant parameters and the equation for computing the
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task duration.
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+
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\f[
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-T_{kernel} = a + b(M^{\alpha_1}\times N^{\beta_1} \times K^{\gamma_1}) + c(M^{\alpha_2}\times N^{\beta_2} \times K^{\gamma_2}) + ...
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+T_{kernel} = a + b(M^{\alpha_1} * N^{\beta_1} * K^{\gamma_1}) + c(M^{\alpha_2} * N^{\beta_2} * K^{\gamma_2}) + ...
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\f]
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+
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\f$M, N, K\f$ are the parameters of the task, added at the task
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creation. These need to be extracted by the <c>cl_perf_func</c>
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function, which should be defined by the user. \f$\alpha, \beta,
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-\gamma\f$ are the exponents defined by user in
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-<c>model->combinations<\c> matrix. Finally, coefficients $\fa, b, c\f$
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+\gamma\f$ are the exponents defined by the user in
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+<c>model->combinations</c> table. Finally, coefficients \f$a, b, c\f$
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are computed automatically at the end of the execution, using least
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squares method of the <c>dgels_</c> LAPACK function.
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<c>examples/basic_examples/mlr.c</c> example provides more details on
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the usage of ::STARPU_MULTIPLE_REGRESSION_BASED models.
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-Computing of the coefficient is done at the end of the execution, and
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-the results are stored in standard codelet perfmodel files. Additional
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-files containing the duration of each task together with the value of
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-each parameter is stored in .starpu/sampling/codelets/tmp/
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-directory. These files are reused when ::STARPU_CALIBRATE
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-environment variable is set to 1, to recompute coefficients based on
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-the current, but also on the previous executions.
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+Coefficients computation is done at the end of the execution, and the
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+results are stored in standard codelet perfmodel files. Additional
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+files containing the duration of task together with the value of each
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+parameter are stored in <c>.starpu/sampling/codelets/tmp/</c>
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+directory. These files are reused when \ref STARPU_CALIBRATE environment
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+variable is set to <c>1</c>, to recompute coefficients based on the current,
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+but also on the previous executions.
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</li>
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