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      organization of physical memory, the frame allocator is always working
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      organization of physical memory, the frame allocator is always working
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      within a context of a particular frame zone. In order to carry out the
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      within a context of a particular frame zone. In order to carry out the
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      allocation requests, the frame allocator is tightly integrated with the
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      allocation requests, the frame allocator is tightly integrated with the
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      buddy system belonging to the zone. The frame allocator is also
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      buddy system belonging to the zone. The frame allocator is also
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      responsible for updating information about the number of free and busy
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      responsible for updating information about the number of free and busy
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      frames in the zone. <figure>
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      frames in the zone. <figure float="1">
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          <mediaobject id="frame_alloc">
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          <mediaobject id="frame_alloc">
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            <imageobject role="pdf">
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            <imageobject role="pdf">
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              <imagedata fileref="images.vector/frame_alloc.pdf" format="PDF" />
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              <imagedata fileref="images.vector/frame_alloc.pdf" format="PDF" />
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            </imageobject>
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            </imageobject>
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      <para>This approach greatly reduces external fragmentation of memory and
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      <para>This approach greatly reduces external fragmentation of memory and
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      helps in allocating bigger continuous blocks of memory aligned to their
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      helps in allocating bigger continuous blocks of memory aligned to their
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      size. On the other hand, the buddy allocator suffers increased internal
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      size. On the other hand, the buddy allocator suffers increased internal
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      fragmentation of memory and is not suitable for general kernel
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      fragmentation of memory and is not suitable for general kernel
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      allocations. This purpose is better addressed by the <link
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      allocations. This purpose is better addressed by the <link
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      linkend="slab">slab allocator</link>.<figure>
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      linkend="slab">slab allocator</link>.<figure float="1">
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          <mediaobject id="buddy_alloc">
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          <mediaobject id="buddy_alloc">
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            <imageobject role="pdf">
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            <imageobject role="pdf">
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              <imagedata fileref="images.vector/buddy_alloc.pdf" format="PDF" />
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              <imagedata fileref="images.vector/buddy_alloc.pdf" format="PDF" />
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            </imageobject>
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            </imageobject>
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      objects from magazines, calling slab cache destructor on them and
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      objects from magazines, calling slab cache destructor on them and
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      putting them back into slabs. When a slab contanins no allocated object,
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      putting them back into slabs. When a slab contanins no allocated object,
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      it is immediately freed.</para>
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      it is immediately freed.</para>
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      <para>
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      <para>
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        <figure>
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        <figure float="1">
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          <mediaobject id="slab_alloc">
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          <mediaobject id="slab_alloc">
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            <imageobject role="pdf">
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            <imageobject role="pdf">
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              <imagedata fileref="images.vector/slab_alloc.pdf" format="PDF" />
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              <imagedata fileref="images.vector/slab_alloc.pdf" format="PDF" />
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            </imageobject>
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            </imageobject>
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