{"id":1394,"date":"2013-07-13T23:55:26","date_gmt":"2013-07-13T15:55:26","guid":{"rendered":"https:\/\/yangtingkun.net\/?p=1394"},"modified":"2013-07-14T22:07:18","modified_gmt":"2013-07-14T14:07:18","slug":"%e7%b3%bb%e7%bb%9f%e5%ad%98%e5%9c%a8%e4%b8%a5%e9%87%8d%e7%9a%84latch-undo-global-data%e7%ad%89%e5%be%85","status":"publish","type":"post","link":"https:\/\/yangtingkun.net\/?p=1394","title":{"rendered":"\u7cfb\u7edf\u5b58\u5728\u4e25\u91cd\u7684latch: undo global data\u7b49\u5f85"},"content":{"rendered":"

\u5ba2\u623710.2.0.5 RAC\u73af\u5883\u51fa\u73b0\u4e86\u4e25\u91cd\u7684latch: undo global data\u7b49\u5f85\u3002<\/p>\n

\u95ee\u9898\u65f6\u523bAWR\u7684TOP\u5982\u4e0b\uff1a<\/p>\n

\n\n\n\n\n\n\n\n\n
\n

Event<\/b><\/p>\n<\/td>\n

\n

Waits<\/b><\/p>\n<\/td>\n

\n

Time(s)<\/b><\/p>\n<\/td>\n

\n

Avg Wait(ms)<\/b><\/p>\n<\/td>\n

\n

% Total Call \u00a0 Time<\/b><\/p>\n<\/td>\n

\n

Wait Class<\/b><\/p>\n<\/td>\n<\/tr>\n

\n

latch: undo \u00a0 global data<\/p>\n<\/td>\n

\n

6,245,400<\/p>\n<\/td>\n

\n

1,372,583<\/p>\n<\/td>\n

\n

220<\/p>\n<\/td>\n

\n

22.0<\/p>\n<\/td>\n

\n

Other<\/p>\n<\/td>\n<\/tr>\n

\n

gc buffer busy<\/p>\n<\/td>\n

\n

114,190,782<\/p>\n<\/td>\n

\n

1,329,749<\/p>\n<\/td>\n

\n

12<\/p>\n<\/td>\n

\n

21.3<\/p>\n<\/td>\n

\n

Cluster<\/p>\n<\/td>\n<\/tr>\n

\n

enq: TX – row \u00a0 lock contention<\/p>\n<\/td>\n

\n

1,377,980<\/p>\n<\/td>\n

\n

685,454<\/p>\n<\/td>\n

\n

497<\/p>\n<\/td>\n

\n

11.0<\/p>\n<\/td>\n

\n

Application<\/p>\n<\/td>\n<\/tr>\n

\n

CPU time<\/p>\n<\/td>\n

\n

\n<\/td>\n

\n

460,041<\/p>\n<\/td>\n

\n

\n<\/td>\n

\n

7.4<\/p>\n<\/td>\n

\n

\n<\/td>\n<\/tr>\n

\n

enq: TX – index \u00a0 contention<\/p>\n<\/td>\n

\n

602,648<\/p>\n<\/td>\n

\n

285,683<\/p>\n<\/td>\n

\n

474<\/p>\n<\/td>\n

\n

4.6<\/p>\n<\/td>\n

\n

Concurrency<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

 <\/p>\n

\u7b49\u5f85\u6700\u660e\u663e\u7684\u662flatch: undo global data\u548cgc buffer busy\uff0c\u540e\u8005\u662fRAC\u4e2d\u6bd4\u8f83\u5e38\u89c1\u7684\u7b49\u5f85\uff0c\u4e5f\u53ef\u4ee5\u6839\u636e\u62a5\u544a\u540e\u9762\u7684SQL\u7b49\u5f85\u90e8\u5206\u5f88\u5bb9\u6613\u5b9a\u4f4d\u5230\u5bfc\u81f4\u95ee\u9898\u7684SQL\u8bed\u53e5\uff0c\u800c\u524d\u8005\u7684\u7b49\u5f85\u5e76\u4e0d\u5e38\u89c1\u3002<\/p>\n

\u6839\u636eMOS\u6587\u6863”LATCH: UNDO GLOBAL DATA” In The Top Wait Events [ID 1451536.1]\u63cf\u8ff0\uff0c\u8fd9\u4e2a\u7b49\u5f85\u548c\u9690\u542b\u53c2\u6570_undo_autotune\u8bbe\u7f6e\u4e3aFALSE\u60c5\u51b5\u4e0b\u7684UNDO\u7a7a\u95f4\u4e0d\u8db3\u6709\u5173<\/p>\n

\u5f53\u524d\u6570\u636e\u5e93\u786e\u5b9e\u5173\u95ed\u4e86_undo_autotune\u529f\u80fd\u3002\u4e14LATCH undo global data\u6700\u591a\u7684\u7b49\u5f85\u53d1\u751f\u5728ktusm_stealext: KSLBEGIN\u5904\uff0c\u8fd9\u8bf4\u660e\u4f1a\u8bdd\u5728\u5bfb\u627e\u65b0\u7684UNDO EXTENTS\u65f6\uff0c\u4e0d\u5f97\u4e0dSteal\u672a\u8fc7\u671f\u7684UNDO EXTENTS\u3002<\/p>\n

\u89e3\u51b3\u65b9\u6848\u6709\u4e09\u4e2a\uff1a\u51cf\u5c11UNDO_RETENTION\u53c2\u6570\u8bbe\u7f6e\u7684\u65f6\u95f4\u957f\u5ea6\uff1b\u589e\u52a0UNDO_TABLESPACE\u7684\u7a7a\u95f4\u5927\u5c0f\uff1b\u5c06_undo_autotune\u9690\u542b\u53c2\u6570\u8bbe\u7f6e\u4e3aTRUE\u3002<\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

\u5ba2\u623710.2.0.5 RAC\u73af\u5883\u51fa\u73b0\u4e86\u4e25\u91cd\u7684latch: undo global data\u7b49\u5f85\u3002 \u95ee\u9898\u65f6\u523bAWR\u7684TOP\u5982\u4e0b\uff1a Event Waits Time(s) Avg Wait(ms) % Total Call \u00a0 Time Wait Class latch: undo \u00a0 global data 6,245,400 1,372,583 220 22.0 Other gc buffer busy 114,190,782 1,329,749 12 21.3 Cluster enq: TX – row … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[5],"tags":[1220,1219,1217,1218],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p2yiY3-mu","_links":{"self":[{"href":"https:\/\/yangtingkun.net\/index.php?rest_route=\/wp\/v2\/posts\/1394"}],"collection":[{"href":"https:\/\/yangtingkun.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/yangtingkun.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/yangtingkun.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/yangtingkun.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1394"}],"version-history":[{"count":1,"href":"https:\/\/yangtingkun.net\/index.php?rest_route=\/wp\/v2\/posts\/1394\/revisions"}],"predecessor-version":[{"id":1395,"href":"https:\/\/yangtingkun.net\/index.php?rest_route=\/wp\/v2\/posts\/1394\/revisions\/1395"}],"wp:attachment":[{"href":"https:\/\/yangtingkun.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1394"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/yangtingkun.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1394"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/yangtingkun.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1394"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}