<\/span><\/h2>\n\n\n\n\u6bcf\u4e2a\u8868\u88abopen\u65f6\uff0c\u4f1a\u4f7f\u75281\u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\u6765\u5904\u7406\u6570\u636e\uff0c\u7b2c\u4e00\u6b21\u6253\u5f00\u65f6\u8fd8\u9700\u89811\u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\uff08file descriptor\uff09\u6765\u5904\u7406\u7d22\u5f15\uff08\u7d22\u5f15\u540e\u7eed\u5171\u4eab\u4f7f\u7528\uff09\u3002\u8868\u6bcf\u6b21\u88ab\u8bbf\u95ee\u5230\u90fd\u4f1a\u88abopen\uff0c\u5982\u679c\u540c\u65f6\u591a\u6b21\u6253\u5f00\uff0c\u6bd4\u5982\u591asession\u7684\u5e76\u53d1\u6216\u8005\u4e00\u4e2aSQL\u5185\u4f7f\u7528\u591a\u6b21\uff0c\u5219\u8ba1\u7b97\u591a\u6b21\u3002<\/p>\n\n\n\n
\u53c2\u6570\u8bbe\u7f6e\u5efa\u8bae\u6839\u636e\u5e76\u53d1\u6570\uff0c\u6bcf\u4e2asession\u6d89\u53ca\u7684\u8868\u6570\u91cf\u8ba1\u7b97\u3002\u6bd4\u5982100\u4e2a\u5e76\u53d1\uff0c\u6bcf\u4e2a\u8bbf\u95eeN\u4e2a\u8868(\u65e0\u8bba\u662f\u5426\u4e3a\u540c\u4e00\u4e2a\u8868),\u90a3\u4e48\u8fd9\u4e2a\u53c2\u6570\u5efa\u8bae\u8bbe\u7f6e\u6210100*N\u3002 \u5f53\u7136\u5b9e\u9645\u8bbe\u7f6e\u65f6\uff0c\u662f\u8981\u8003\u8651\u7cfb\u7edf\u4f7f\u7528\u7684\u91cf\uff0c\u6bd4\u5982\u4e2d\u95f4\u4e34\u65f6\u8868\u3002<\/p>\n\n\n\n
\u5982\u679c\u8868OPEN\u6570\u91cf\u8d85\u8fc7\u4e86\u53c2\u6570\uff0c\u4e14\u6ca1\u6709\u53ef\u56de\u6536\u7684(LRU)\uff0c\u6709\u53ef\u80fd\u4e34\u65f6\u6253\u5f00\u8868\uff0c\u4f7f\u7528\u540e\u7acb\u5373\u91ca\u653e\u3002<\/p>\n\n\n\n
\u8be5\u53c2\u6570\u6d89\u53ca\u5230\u4e86open_files\u7684\u64cd\u4f5c\u7cfb\u7edf\u53c2\u6570\u3002\u8fc7\u5927\u4f1a\u5360\u7528\u592a\u591a\u5185\u5b58\uff0c\u8fc7\u5c0f\u4f1a\u6bcf\u6b21\u90fd\u6253\u5f00\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u5f71\u54cd\u6027\u80fd\u3002<\/p>\n\n\n\n
gbase> SHOW GLOBAL VARIABLES LIKE '%table_open_cache%';\n+------------------+-------+\n| Variable_name | Value |\n+------------------+-------+\n| table_open_cache | 64 |\n+------------------+-------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u67e5\u770b\u5f53\u524d\u6253\u5f00\u7684table\u6570\u91cf<\/span><\/h2>\n\n\n\n\u5982\u679c\u4e00\u76f4\u662f\u6ee1\u7684\uff0c\u53ef\u4ee5\u8003\u8651\u589e\u52a0table_open_cache\u53c2\u6570\u4e86\u3002<\/p>\n\n\n\n
gbase> SHOW GLOBAL STATUS LIKE 'Opened_tables';\n+---------------+-------+\n| Variable_name | Value |\n+---------------+-------+\n| Opened_tables | 27 |\n+---------------+-------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u5b9a\u4e49\u8868\u7ed3\u6784\u7f13\u51b2\u6570\u91cf table_definition_cache<\/span><\/h2>\n\n\n\n\u53ef\u4ee5\u7f13\u51b2\u8868\u7684frm\u7ed3\u6784\u3002<\/p>\n\n\n\n
\u53c2\u6570\u8bbe\u7f6e\u5efa\u8bae\u6839\u636e\u5b9e\u9645\u8868\u7684\u6570\u91cf\uff0c\u7279\u522b\u65f6\u8fd1\u671f\u5e38\u7528\u7684\u8868\u6570\u91cf\u8fdb\u884c\u7f13\u51b2\uff0c\u907f\u514d\u8fc7\u5927\u800c\u6d6a\u8d39\u5185\u5b58\uff08\u4f46\u4e00\u534afrm\u8868\u7ed3\u6784\u90fd\u5f88\u5c0f\uff0cK\u51e0\u500d\uff0c1\u4e07\u4e2a\u4e5f\u5c3110M)\uff0c\u8fc7\u5c0f\u5219\u6bcf\u6b21\u4ece\u78c1\u76d8\u8bfb\u53d6\u5f71\u54cd\u6027\u80fd\u3002<\/p>\n\n\n\n
gbase> SHOW GLOBAL VARIABLES LIKE '%table_definition_cache%';\n+------------------------+-------+\n| Variable_name | Value |\n+------------------------+-------+\n| table_definition_cache | 256 |\n+------------------------+-------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u67e5\u770b\u5f53\u524d\u6253\u5f00\u7684\u8868\u5b9a\u4e49<\/span><\/h2>\n\n\n\nOpened_table_definitions \u6253\u5f00\u8fc7\u7684
Open_table_definitions \u5f53\u524d\u6253\u5f00\u7684\u3002<\/p>\n\n\n\n
gbase> show status like '%table_def%';\n+--------------------------+-------+\n| Variable_name | Value |\n+--------------------------+-------+\n| Open_table_definitions | 303 |\n| Opened_table_definitions | 72 |\n+--------------------------+-------+\n2 rows in set (Elapsed: 00:00:00.00)\n....\ngbase> show status like '%table_def%';\n+--------------------------+-------+\n| Variable_name | Value |\n+--------------------------+-------+\n| Open_table_definitions | 547 |\n| Opened_table_definitions | 1249 |\n+--------------------------+-------+\n2 rows in set (Elapsed: 00:00:00.00)\n\n<\/code><\/pre>\n\n\n\n\u5982\u679c\u5f53\u524d\u8981\u6253\u5f00\u7684\u8d85\u8fc7\u4e86\u524d\u9762\u5b9a\u4e49\u7684\u6700\u5927\u503c\uff0c\u4e14\u5728prepare \u7684SQL\u91cc\uff0c\u4f1a\u62a5 Prepared statement needs to be re-prepared \u9519\u8bef\u3002<\/p>\n\n\n\n
<\/span>\u67e5\u770b\u5f53\u524d\u6253\u5f00\u7684\u8868<\/span><\/h2>\n\n\n\ngbase> show open tables;\n+------------+-------------------+--------+-------------+\n| Database | Table | In_use | Name_locked |\n+------------+-------------------+--------+-------------+\n| testdb | t1 | 0 | 0 |\n| testdb | t2 | 0 | 0 |\n| gbase | event | 0 | 0 |\n| gclusterdb | audit_log_express | 0 | 0 |\n+------------+-------------------+--------+-------------+\n4 rows in set (Elapsed: 00:00:00.00)\ngbase> show open tables from testdb;\n+----------+-------+--------+-------------+\n| Database | Table | In_use | Name_locked |\n+----------+-------+--------+-------------+\n| testdb | t1 | 0 | 0 |\n| testdb | t2 | 0 | 0 |\n+----------+-------+--------+-------------+\n2 rows in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>","protected":false},"excerpt":{"rendered":"\u5357\u5927\u901a\u7528gbase\u5bf9\u6bcf\u4e2a\u8bbf\u95ee\u7684\u8868\uff0c\u90fd\u5c06\u5176\u8868\u7ed3\u6784(frm)\u8fdb\u884c\u7f13\u51b2\uff0c\u6700\u5927\u7f13\u51b2\u6570\u91cf\u901a\u8fc7table_definition_cache\u5b9a\u4e49\u3002\u5f53\u8868\u6bcf\u6b21\u88ab\u8bbf\u95ee\u90fd\u88ab\u6253\u5f00\u5e76\u7f13\u51b2\uff0c\u6700\u5927\u7f13\u51b2\u6570\u91cf\u901a\u8fc7table_open_cache\u5b9a\u4e49\u3002<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[],"class_list":["post-1983","post","type-post","status-publish","format-standard","hentry","category-gbase8a"],"_links":{"self":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/1983","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/comments?post=1983"}],"version-history":[{"count":17,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/1983\/revisions"}],"predecessor-version":[{"id":8141,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/1983\/revisions\/8141"}],"wp:attachment":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/media?parent=1983"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/categories?post=1983"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/tags?post=1983"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}