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+{"body":"<div><div><div class=\"hue-doc-title\">SCRATCH_LIMIT Query Option</div><div><p>\n Specifies the maximum amount of disk storage, in bytes, that any Impala query can consume\n on any host using the <q>spill to disk</q> mechanism that handles queries that exceed\n the memory limit.\n </p><p><b>Syntax:</b></p><p>\n Specify the size in bytes, or with a trailing <span class=\"hue-doc-codeph\">m</span> or <span class=\"hue-doc-codeph\">g</span> character to indicate\n megabytes or gigabytes. For example:\n </p><div class=\"hue-doc-codeblock\">-- 128 megabytes.\nset SCRATCH_LIMIT=134217728\n\n-- 512 megabytes.\nset SCRATCH_LIMIT=512m;\n\n-- 1 gigabyte.\nset SCRATCH_LIMIT=1g;\n</div><p><b>Usage notes:</b></p><p>\n A value of zero turns off the spill to disk feature for queries\n in the current session, causing them to fail immediately if they\n exceed the memory limit.\n </p><p>\n The amount of memory used per host for a query is limited by the\n <span class=\"hue-doc-codeph\">MEM_LIMIT</span> query option.\n </p><p>\n The more Impala daemon hosts in the cluster, the less memory is used on each host,\n and therefore also less scratch space is required for queries that\n exceed the memory limit.\n </p><p><b>Type:</b> numeric, with optional unit specifier\n </p><p><b>Default:</b> -1 (amount of spill space is unlimited)\n </p><p><b>Related information:</b></p><p><a class=\"hue-doc-external-link\" href=\"https://www.cloudera.com/documentation/enterprise/latest/topics/impala_scalability.html#spill_to_disk\" target=\"_blank\">SQL Operations that Spill to Disk</a>,\n <a class=\"hue-doc-internal-link\" href=\"javascript:void(0);\" data-doc-ref=\"topics/impala_mem_limit.xml\" data-doc-anchor-id=\"mem_limit\">MEM_LIMIT Query Option</a></p></div></div></div>","title":"SCRATCH_LIMIT Query Option"}
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