\u9501\u5347\u7ea7\u7684\u987a\u5e8f\uff1a\u504f\u5411\u9501-> \u8f7b\u91cf\u7ea7\u9501->\u91cd\u91cf\u7ea7\u9501<\/p>\n
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\n2\u3001\t\u5f53\u4e24\u4e2a\u7ebf\u7a0b\u5b58\u5728\u7ade\u4e89\u5173\u7cfb\u65f6\uff0c\u7b2c\u4e00\u4e2a\u7ebf\u7a0b\u62e5\u6709\u504f\u5411\u9501\u65f6\uff0c\u7b2c\u4e8c\u4e2a\u7ebf\u7a0b\u4f1a\u53bb\u64a4\u9500\u7ebf\u7a0b\u4e00\u7684\u9501, \u64a4\u9500\u6210\u529f\uff08\u6709\u4e24\u79cd\u60c5\u51b5\u80fd\u6210\u529f\uff0c\u7b2c\u4e00\u7ebf\u7a0b\u4e00\u76f4\u63a5\u7ed3\u675f\uff0c\u7b2c\u4e8c\u7ebf\u7a0b\u4e00\u5230\u8fbe\u4e86\u4e00\u4e2a\u5168\u5c40\u5b89\u5168\u70b9 safepoint, synchroized\u6e90\u7801\u4f1a\u5224\u5b9ais_at_safepoint\uff09,\u7ebf\u7a0b\u4e8c\u83b7\u5f97\u504f\u5411\u9501\uff0c\u64a4\u9500\u5931\u8d25\uff0c\u7ebf\u7a0b\u4e8c\u8fdb\u884c\u9501\u5347\u7ea7\uff0c\u5347\u7ea7\u5230\u8f7b\u91cf\u7ea7\u9501
\n\u6ce8\u610f\uff1a\u5982\u679c\u8981\u83b7\u53d6\u9501\u5bf9\u8c61\u7684hascode\u662f\u65e0\u6cd5\u4f7f\u7528\u504f\u5411\u9501\u7684\uff08\u56e0\u4e3a\u504f\u5411\u9501\u7684\u5bf9\u8c61\u5934\u53ea\u5b58\u4e86\u7ebf\u7a0bID 23bit\u548cEpoch2bit,\u65e0\u9501\u72b6\u6001\u524d25bit\u7528\u6765\u5b58\u50a8\u5bf9\u8c61\u7684hascode,\u4f1a\u76f4\u63a5\u4f7f\u7528\u91cd\u91cf\u7ea7\u9501\uff0c\u5bf9\u8c61 hash \u503c\u4f1a\u5b58\u5728 ObjectMonitor _header markOop \u5bf9\u8c61\u5934\uff09\u4e2d\uff09<\/p>\n
class markOopDesc:\toopDesc {
\n\u300dV\u201d\uff1a\u2022:
\n\/\/ Conversion uintptr_t valueO\t{\t(uintptr_t) this; }
\npublic:
\ni__ \/\/ Constants\t\t.<\/p>\n
};
\n\u5ef6\u4f38\uff1a\u6bcf\u4e00\u4e2ajava\u5bf9\u8c61\u6700\u7ec8\u90fd\u4f1a\u8f6c\u6362\u4e3ajvm\u865a\u62df\u673a\u7684\u4e00\u4e2ainstanceOopDesc\u5bf9\u8c61\uff0c\u5f15\u7528jvm instanceOopDesc \u5bf9\u8c61\u7684\u4e00\u53e5\u6ce8\u91ca\uff1a"\/\/ An instanceOop is an instance of a Java Class"
\n\u504f\u5411\u9501\u7684\u83b7\u5f97\u548c\u6487\u9500\u6d41\u7a0b<\/p>\n
\u8f7b\u91cf\u7ea7\u9501: \u4f1a\u5728\u7ebf\u7a0b\u6808\u5e27\u4e2d\u5206\u914d\u4e00\u4e2alock record\u7a7a\u95f4\u5b58\u50a8\u7ebf\u7a0b\u5bf9\u8c61\u5934\uff0c\u7ebf\u7a0b\u5bf9\u8c61\u5934\u5b58\u50a8\u6307\u5411lock record \u7684\u6307\u9488\uff0c\u7136\u540e\u56de\u901a\u8fc7cas\u64cd\u4f5c\uff0c\u66ff\u6362\u5bf9\u8c61\u5934\u7684\u6307\u9488\uff0c\u66ff\u6362\u6210\u529f\u5f53\u524d\u7ebf\u7a0b\u83b7\u5f97\u8f7b\u91cf\u7ea7\u9501\uff0c\u66ff\u6362\u5931 \u8d25\uff0c\u8fdb\u884c\u81ea\u65cb\uff08\u591a\u6b21cas\uff1a 1.6\u4ee5\u524d10\u6b21\uff0c1.6\u4ee5\u540e\u81ea\u9002\u5e94\u81ea\u65cb\uff0c\u6839\u636e\u4e0a\u4e00\u6b21\u81ea\u65cb\u83b7\u5f97\u9501\u7684\u65f6 \u95f4\uff0c\u51b3\u5b9a\u5f53\u524d\u81ea\u65cb\u7684\u6b21\u6570\uff09\uff0c\u81ea\u65cb\u5931\u8d25\uff0c\u9501\u81a8\u80c0\u5347\u7ea7\u4e3a\u91cd\u91cf\u7ea7\u9501<\/p>\n
\u91cd\u91cf\u7ea7\u9501\uff1a
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\n2\u3001\t\u5360\u6709\u4e14\u7b49\u5f85\uff0c\u7ebf\u7a0bT1\u5df2\u7ecf\u53d6\u5f97\u5171\u4eab\u8d44\u6e90X,\u5728\u7b49\u5f85\u5171\u4eab\u8d44\u6e90Y\u7684\u65f6\u5019\uff0c\u4e0d\u91ca\u653e\u5171\u4eab\u8d44\u6e90X;
\n3\u3001\t\u4e0d\u53ef\u62a2\u5360\uff0c\u5176\u4ed6\u7ebf\u7a0b\u4e0d\u80fd\u5f3a\u884c\u62a2\u5360\u7ebf\u7a0bT1\u5360\u6709\u7684\u8d44\u6e90;
\n4,\u5faa\u73af\u7b49\u5f85\uff0c\u7ebf\u7a0bT1\u7b49\u5f85\u7ebf\u7a0bT2\u5360\u6709\u7684\u8d44\u6e90\uff0c\u7ebf\u7a0bT2\u7b49\u5f85\u7ebf\u7a0bT1\u5360\u6709\u7684\u8d44\u6e90\uff0c\u5c31\u662f\u5faa\u73af \u7b49\u5f85\u3002
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\n2\u3001\t\u8f7b\u91cf\u7ea7\u9501\u662f\u7531\u504f\u5411\u6240\u5347\u7ea7\u6765\u7684\uff0c\u504f\u5411\u9501\u8fd0\u884c\u5728\u4e00\u4e2a\u7ebf\u7a0b\u8fdb\u5165\u540c\u6b65\u5757\u7684\u60c5\u51b5\u4e0b\uff0c\u5f53\u7b2c\u4e8c\u4e2a\u7ebf \u7a0b\u52a0\u5165\u9501\u4e89\u7528\u7684\u65f6\u5019\uff0c\u8f7b\u91cf\u7ea7\u9501\u5c31\u4f1a\u5347\u7ea7\u4e3a\u91cd\u91cf\u7ea7\u9501;
\n3\u3001\t\u91cd\u91cf\u7ea7\u9501\u662fsynchronized ,\u662fJava\u865a\u62df\u673a\u4e2d\u6700\u4e3a\u57fa\u7840\u7684\u9501\u5b9e\u73b0\u3002\u5728\u8fd9\u79cd\u72b6\u6001\u4e0b\uff0cJava \u865a\u62df\u673a\u4f1a\u963b\u585e\u52a0\u9501\u5931\u8d25\u7684\u7ebf\u7a0b\uff0c\u5e76\u4e14\u5728\u76ee\u6807\u9501\u88ab\u91ca\u653e\u7684\u65f6\u5019\uff0c\u5524\u9192\u8fd9\u4e9b\u7ebf\u7a0b\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u9501\u5347\u7ea7\u7684\u987a\u5e8f\uff1a\u504f\u5411\u9501-> \u8f7b\u91cf\u7ea7\u9501->\u91cd\u91cf\u7ea7\u9501 \u504f\u5411\u9501\uff1a 1\u3001 \u4f7f\u7528\u4e86 synchronized\u5173 […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[118],"tags":[],"class_list":["post-10871","post","type-post","status-publish","format-standard","hentry","category-java"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10871","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=10871"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10871\/revisions"}],"predecessor-version":[{"id":10872,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/10871\/revisions\/10872"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=10871"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=10871"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=10871"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}