docs/build/plain-html/topics/impala_max_mem_estimate_for_admission.html - impala - Git at Google

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   <h1 class="title topictitle1" id="ariaid-title1">MAX_MEM_ESTIMATE_FOR_ADMISSION Query Option</h1>


   <div class="body conbody">

     <p class="p">
       Use the <code class="ph codeph">MAX_MEM_ESTIMATE_FOR_ADMISSION</code> query option to set an upper limit
       on the memory estimates of a query as a workaround for over-estimates precluding a query
       from being admitted.
     </p>


     <p class="p">
       The query option takes effect when all of the below conditions are met:
     </p>


     <ul class="ul">
       <li class="li">
         Memory-based admission control is enabled for the pool.
       </li>


       <li class="li">
         The <code class="ph codeph">MEM_LIMIT</code> query option is not set at the query, session, resource
         pool, or global level.
       </li>

     </ul>


     <p class="p">
       When the above conditions are met, MIN(<code class="ph codeph">MAX_MEM_ESTIMATE_FOR_ADMISSION</code>,
       mem_estimate) is used for admission control.
     </p>


     <p class="p">
       Setting the <code class="ph codeph">MEM_LIMIT</code> query option is usually a better option. Use the
       <code class="ph codeph">MAX_MEM_ESTIMATE_FOR_ADMISSION</code> query option when it is not feasible to
       set <code class="ph codeph">MEM_LIMIT</code> for each individual query.
     </p>


     <p class="p">
         <strong class="ph b">Type:</strong> integer
       </p>


     <p class="p">
         <strong class="ph b">Default:</strong>
       </p>


     <p class="p">
       <strong class="ph b">Added in:</strong> <span class="keyword">Impala 3.1</span>
     </p>


     <p class="p">
         <strong class="ph b">Usage notes:</strong>
       </p>


     <p class="p">
         <strong class="ph b">Related information:</strong>
       </p>


   </div>


 <div class="related-links">
 <div class="familylinks">
 <div class="parentlink"><strong>Parent topic:</strong> <a class="link" href="../topics/impala_query_options.html">Query Options for the SET Statement</a></div>
 </div>
 </div></body>
 </html>
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	<head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />

	<meta name="copyright" content="(C) Copyright 2023" />
	<meta name="DC.rights.owner" content="(C) Copyright 2023" />
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	<meta name="DC.Title" content="MAX_MEM_ESTIMATE_FOR_ADMISSION Query Option" />
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	<meta name="DC.Identifier" content="max_mem_estimate_for_admission" />
	<link rel="stylesheet" type="text/css" href="../commonltr.css" />
	<title>MAX_MEM_ESTIMATE_FOR_ADMISSION Query Option</title>
	</head>
	<body id="max_mem_estimate_for_admission">


	<h1 class="title topictitle1" id="ariaid-title1">MAX_MEM_ESTIMATE_FOR_ADMISSION Query Option</h1>






	<div class="body conbody">

	<p class="p">
	Use the <code class="ph codeph">MAX_MEM_ESTIMATE_FOR_ADMISSION</code> query option to set an upper limit
	on the memory estimates of a query as a workaround for over-estimates precluding a query
	from being admitted.
	</p>


	<p class="p">
	The query option takes effect when all of the below conditions are met:
	</p>


	<ul class="ul">
	<li class="li">
	Memory-based admission control is enabled for the pool.
	</li>


	<li class="li">
	The <code class="ph codeph">MEM_LIMIT</code> query option is not set at the query, session, resource
	pool, or global level.
	</li>

	</ul>


	<p class="p">
	When the above conditions are met, MIN(<code class="ph codeph">MAX_MEM_ESTIMATE_FOR_ADMISSION</code>,
	mem_estimate) is used for admission control.
	</p>


	<p class="p">
	Setting the <code class="ph codeph">MEM_LIMIT</code> query option is usually a better option. Use the
	<code class="ph codeph">MAX_MEM_ESTIMATE_FOR_ADMISSION</code> query option when it is not feasible to
	set <code class="ph codeph">MEM_LIMIT</code> for each individual query.
	</p>


	<p class="p">
	<strong class="ph b">Type:</strong> integer
	</p>


	<p class="p">
	<strong class="ph b">Default:</strong>
	</p>


	<p class="p">
	<strong class="ph b">Added in:</strong> <span class="keyword">Impala 3.1</span>
	</p>


	<p class="p">
	<strong class="ph b">Usage notes:</strong>
	</p>


	<p class="p">
	<strong class="ph b">Related information:</strong>
	</p>


	</div>


	<div class="related-links">
	<div class="familylinks">
	<div class="parentlink"><strong>Parent topic:</strong> <a class="link" href="../topics/impala_query_options.html">Query Options for the SET Statement</a></div>
	</div>
	</div></body>
	</html>