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          <listitem>
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          <listitem>
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             Allowing, in general, to load and execute two programs that are linked on the same address without complicated relocations.
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             Allowing, in general, to load and execute two programs that are linked on the same address without complicated relocations.
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          </listitem>
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          </listitem>
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        </itemizedlist></para>
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        </itemizedlist></para>
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<para><!--
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                TLB shootdown ASID/ASID:PAGE/ALL.
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                TLB shootdown requests can come in asynchroniously
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                so there is a cache of TLB shootdown requests. Upon cache overflow TLB shootdown ALL is executed
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                <para>
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                        Address spaces. Address space area (B+ tree). Only for uspace. Set of syscalls (shrink/extend etc).
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                        Special address space area type - device - prohibits shrink/extend syscalls to call on it.
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                        Address space has link to mapping tables (hierarchical - per Address space, hash - global tables).
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                </para>
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--></para>
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    </section>
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    </section>
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    <section>
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    <section>
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      <title>Paging</title>
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      <title>Paging</title>
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      <para>Virtual memory is usually using paged memory model, where virtual
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      <para>Virtual memory is usually using paged memory model, where virtual
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      memory address space is divided into the <emphasis>pages</emphasis>
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      memory address space is divided into the <emphasis>pages</emphasis>
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      (usually having size 4096 bytes) and physical memory is divided into the
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      (usually having size 4096 bytes) and physical memory is divided into the
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      frames (same sized as a page, of course). Each page may be mapped to some
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      frames (same sized as a page, of course). Each page may be mapped to some
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      frame and then, upon memory access to the virtual address, CPU performs
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      frame and then, upon memory access to the virtual address, CPU performs
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        <para>- vztah task ~ adresovy prostor: teoreticky existuje moznost, ze
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        <para>- vztah task ~ adresovy prostor: teoreticky existuje moznost, ze
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        je adresovy prostor sdilen vice tasky, avsak tuto moznost nepouzivame
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        je adresovy prostor sdilen vice tasky, avsak tuto moznost nepouzivame
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        a neni ani nijak osetrena. Tim padem plati, ze kazdy task ma vlastni
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        a neni ani nijak osetrena. Tim padem plati, ze kazdy task ma vlastni
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        adresovy prostor</para>
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        adresovy prostor</para>
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      </section>
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      </section>
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    </section>
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    </section>
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    <section>
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    <section>
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      <title>Virtual address translation</title>
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      <title>Virtual address translation</title>
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