The Silent Healer of Your Database \ud83d\udee0\ufe0f<\/p>\n\n\n\n
\ud83e\udde0 What Is SMON?<\/strong> Think of SMON as the database\u2019s janitor and doctor<\/strong> \u2014 it keeps things clean, consistent, and recovers what\u2019s broken.<\/p>\n\n\n\n SMON is always working in the background \u2014 but you can monitor undo space and rollback activity<\/strong> using views like The Silent Healer of Your Database \ud83d\udee0\ufe0f \ud83e\udde0 What Is SMON?The System Monitor Process (SMON) is a background process that quietly handles critical recovery and cleanup tasks to keep your Oracle Database running smoothly and consistently. Think of SMON as the database\u2019s janitor and doctor \u2014 it keeps things clean, consistent, and recovers what\u2019s broken. […]<\/p>\n","protected":false},"template":"","meta":{"googlesitekit_rrm_CAowu461DA:productID":""},"categories":[960,952],"class_list":["post-3726","cposts","type-cposts","status-publish","hentry","category-getting-started-with-oracle-dba","category-notes"],"_links":{"self":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/cposts\/3726","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/cposts"}],"about":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/types\/cposts"}],"wp:attachment":[{"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/media?parent=3726"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/w3buddy.com\/blog\/wp-json\/wp\/v2\/categories?post=3726"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
The System Monitor Process (SMON)<\/strong> is a background process that quietly handles critical recovery and cleanup tasks<\/strong> to keep your Oracle Database running smoothly and consistently.<\/p>\n\n\n\n\ud83d\udd01 What SMON Does<\/h3>\n\n\n\n
Task<\/strong><\/th> Description<\/strong><\/th><\/tr><\/thead> \ud83e\uddf9 Undo Cleanup<\/strong><\/td> Shrinks undo segments based on usage; rolls back large, terminated transactions. Can use parallel query slaves for efficiency.<\/td><\/tr> \ud83e\uddfe Data Dictionary Cleanup<\/strong><\/td> Fixes inconsistent or transient metadata states in the system catalog.<\/td><\/tr> \u23f1\ufe0f SCN-Time Mapping<\/strong><\/td> Maintains a table mapping System Change Numbers (SCN) to timestamps \u2014 critical for Flashback queries.<\/td><\/tr> \u2764\ufe0f Error Resilience<\/strong><\/td> Can recover from internal and external errors during background tasks without failing.<\/td><\/tr> \ud83e\uddd1\u200d\ud83e\udd1d\u200d\ud83e\uddd1 Oracle RAC Recovery<\/strong><\/td> In RAC setups, SMON from one instance can recover failed instances.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n \u2699\ufe0f Where SMON Runs<\/h3>\n\n\n\n
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\ud83d\udca1 DBA Tip of the Day<\/strong><\/h3>\n\n\n\n
V$UNDOSTAT<\/code> and DBA_HIST_UNDOSTAT<\/code> to help SMON do its job more efficiently.<\/p>\n","protected":false},"excerpt":{"rendered":"