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     <h4 class="title">
      <a name="innodb-information-schema-innodb_cmpmem">
      </a>
      17.15.1.2 INNODB_CMPMEM and INNODB_CMPMEM_RESET
     </h4>
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  <a class="indexterm" name="idm46045151387904">
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  <a class="indexterm" name="idm46045151386512">
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  <a class="indexterm" name="idm46045151385120">
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  <p>
   The
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM
    </code>
   </a>
   and
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM_RESET
    </code>
   </a>
   tables provide
        status information about compressed pages that reside in the
        buffer pool. Please consult
   <a class="xref" href="innodb-compression.html" title="17.9 InnoDB Table and Page Compression">
    Section 17.9, “InnoDB Table and Page Compression”
   </a>
   for further information on compressed tables and the use of the
        buffer pool. The
   <a class="link" href="information-schema-innodb-cmp-table.html" title="28.4.6 The INFORMATION_SCHEMA INNODB_CMP and INNODB_CMP_RESET Tables">
    <code class="literal">
     INNODB_CMP
    </code>
   </a>
   and
   <a class="link" href="information-schema-innodb-cmp-table.html" title="28.4.6 The INFORMATION_SCHEMA INNODB_CMP and INNODB_CMP_RESET Tables">
    <code class="literal">
     INNODB_CMP_RESET
    </code>
   </a>
   tables should
        provide more useful statistics on compression.
  </p>
  <h5>
   <a name="idm46045151378912">
   </a>
   Internal Details
  </h5>
  <p>
   <code class="literal">
    InnoDB
   </code>
   uses a
   <a class="link" href="glossary.html#glos_buddy_allocator" title="buddy allocator">
    buddy allocator
   </a>
   system to manage memory allocated to
   <a class="link" href="glossary.html#glos_page_size" title="page size">
    pages of various sizes
   </a>
   ,
        from 1KB to 16KB. Each row of the two tables described here
        corresponds to a single page size.
  </p>
  <p>
   The
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM
    </code>
   </a>
   and
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM_RESET
    </code>
   </a>
   tables have
        identical contents, but reading from
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM_RESET
    </code>
   </a>
   resets the
        statistics on relocation operations. For example, if every 60
        minutes you archived the output of
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM_RESET
    </code>
   </a>
   , it would show
        the hourly statistics. If you never read
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM_RESET
    </code>
   </a>
   and monitored
        the output of
   <a class="link" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    <code class="literal">
     INNODB_CMPMEM
    </code>
   </a>
   instead, it would show the cumulative statistics since
   <code class="literal">
    InnoDB
   </code>
   was started.
  </p>
  <p>
   For the table definition, see
   <a class="xref" href="information-schema-innodb-cmpmem-table.html" title="28.4.7 The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables">
    Section 28.4.7, “The INFORMATION_SCHEMA INNODB_CMPMEM and INNODB_CMPMEM_RESET Tables”
   </a>
   .
  </p>
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