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    </section>

    </section>

    <section id="frame_allocator">

    <section id="frame_allocator">

      <title>Frame allocator</title>

      <title>Frame allocator</title>

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            <imagedata fileref="images/frame_alloc.png" format="PNG" />

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          </imageobject>

          <imageobject role="fop">

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      <formalpara>

      <formalpara>

        <title>Overview</title>

        <title>Overview</title>

        <para>Frame allocator provides physical memory allocation for the

        <para>Frame allocator provides physical memory allocation for the

      <title>Buddy allocator</title>

      <title>Buddy allocator</title>

      <section>

      <section>

        <title>Overview</title>

        <title>Overview</title>

            <imageobject role="html">

            <imageobject role="html">

              <imagedata fileref="images/buddy_alloc.png" format="PNG" />

              <imagedata fileref="images/buddy_alloc.png" format="PNG" />

            </imageobject>

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        <para>In the buddy allocator, the memory is broken down into

        <para>In the buddy allocator, the memory is broken down into

        power-of-two sized naturally aligned blocks. These blocks are

        power-of-two sized naturally aligned blocks. These blocks are

        organized in an array of lists, in which the list with index i

        organized in an array of lists, in which the list with index i

        contains all unallocated blocks of size

        contains all unallocated blocks of size

      </section>

      </section>

      <section>

      <section>

        <title>Implementation</title>

        <title>Implementation</title>

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            <imageobject role="html">

              <imagedata fileref="images/slab_alloc.png" format="PNG" />

              <imagedata fileref="images/slab_alloc.png" format="PNG" />

            </imageobject>

            </imageobject>

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            </imageobject>

        url="http://www.usenix.org/events/usenix01/full_papers/bonwick/bonwick_html/">

        url="http://www.usenix.org/events/usenix01/full_papers/bonwick/bonwick_html/">

        with the following exceptions: <itemizedlist>

        with the following exceptions: <itemizedlist>

            <listitem>

            <listitem>

            </listitem>

            </listitem>

            <listitem>

            <listitem>

               empty magazines are deallocated when not needed (in Solaris they are held in linked list in slab cache)

               empty magazines are deallocated when not needed (in Solaris they are held in linked list in slab cache)

            </listitem>

            </listitem>

        <section>

        <section>

          <title>Magazine layer</title>

          <title>Magazine layer</title>

          <para>Due to the extensive bottleneck on SMP architures, caused by

          <para>Due to the extensive bottleneck on SMP architures, caused by

          allocation requests serialized, a new layer was introduced to the

          allocation requests serialized, a new layer was introduced to the

          classic slab allocator design. Slab allocator was extended to

          classic slab allocator design. Slab allocator was extended to

          support per-CPU caches 'magazines' to achieve good SMP scaling.

          support per-CPU caches 'magazines' to achieve good SMP scaling.

          <termdef>Slab SMP perfromance bottleneck was resolved by introducing

          <termdef>Slab SMP perfromance bottleneck was resolved by introducing

          a per-CPU caching scheme called as <glossterm>magazine

          a per-CPU caching scheme called as <glossterm>magazine