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@@ -13,38 +13,29 @@ Scratch can be built on many different systems, it is impossible to
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provide accurate time estimates. The biggest package (Glibc) will
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take approximately 20 minutes on the fastest systems, but could take
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up to three days on slower systems! Instead of providing actual times,
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-the Static Build Unit (SBU) measure will be
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+the Standard Build Unit (SBU) measure will be
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used instead.</para>
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<para>The SBU measure works as follows. The first package to be compiled
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-from this book is the statically-linked Binutils in <xref
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-linkend="chapter-temporary-tools"/>. The time it takes to compile
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-this package is what will be referred to as the Static Build Unit
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-or SBU. All other compile times will be expressed relative to this
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-time.</para>
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+from this book is Binutils in <xref linkend="chapter-temporary-tools"/>. The
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+time it takes to compile this package is what will be referred to as the
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+Standard Build Unit or SBU. All other compile times will be expressed relative
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+to this time.</para>
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<para>For example, consider a package whose compilation time is 4.5
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SBUs. This means that if a system took 10 minutes to compile and
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-install the static Binutils, it will take
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-<emphasis>approximately</emphasis> 45 minutes to build this example
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-package. Fortunately, most build times are shorter than the one
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-for Binutils.</para>
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+install the first pass of Binutils, it will take
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+<emphasis>approximately</emphasis> 45 minutes to build this example package.
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+Fortunately, most build times are shorter than the one for Binutils.</para>
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-<para>Please note that if the system compiler on the host is GCC-2.x based, the
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-SBUs listed may be somewhat understated. This is because the SBU is
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-based on the very first package, compiled with the old GCC, while the
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-rest of the system is compiled with the newer GCC-&gcc-version; (which is
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-known to be approximately 30 percent slower). SBUs are also not
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-highly accurate for Symmetric Multi-Processor (SMP)-based machines.</para>
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+<para>In general, SBUs are not entirely accurate because they depend on many
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+factors, not just the GCC version. Note that on Symmetric Multi-Processor
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+(SMP)-based machines, SBUs are even less accurate. They are provided here to
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+give an estimate of how long it might take to install a package, but the numbers
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+can vary by as much as dozens of minutes in some cases.</para>
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<para>To view actual timings for a number of specific machines, we recommend
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<ulink url="&lfs-root;~bdubbs/"/>.</para>
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-<para>In general, SBUs are not very accurate because they depend on many
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-factors, not just the GCC version. They are provided
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-here to give an estimate of how long it might take to
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-install a package, but the numbers can vary by as much as dozens of
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-minutes in some cases.</para>
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-
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</sect1>
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