\n\t\u73b0\u4ee3\u8ba1\u7b97\u673a\u4e2d\uff0cCPU \u5bf9\u5185\u5b58\u7684\u8bbf\u95ee\u901f\u5ea6\u8981\u6bd4\u4ece\u78c1\u76d8\u7684\u901f\u5ea6\u5feb\u5343\u500d\uff0c\u56e0\u6b64 Oracle \u5bf9\u4e8e\u6570\u636e\u7684\u8bbf\u95ee \u4e5f\u5c3d\u91cf\u90fd\u5728\u5185\u5b58\u4e2d\u5b8c\u6210\uff0c\u800c\u4e0d\u662f\u76f4\u63a5\u4fee\u6539\u786c\u76d8\u4e0a\u7684\u6570\u636e\u3002\u5185\u5b58\u5185\u5bb9\u5728\u5408\u9002\u7684\u65f6\u5019\u518d\u540c\u6b65\u5230\u78c1\u76d8\u3002 Oracle \u5229\u7528\u5185\u5b58\u6765\u514b\u670d\u78c1\u76d8 IO\u7684\u675f\u7f1a\uff0c\u5728\u5185\u5b58\u4e2d\u8fdb\u884c\u6d3b\u52a8\u8d8a\u591a\uff0c\u7cfb\u7edf\u6027\u80fd\u8d8a\u597d\uff0c\u53cd\u4e4b\uff0c\u5728\u78c1\u76d8\u4e0a\u8fdb \u884c\u7684\u64cd\u4f5c\u8d8a\u591a\uff0c\u7cfb\u7edf\u6027\u80fd\u8d8a\u5dee\u3002\n<\/p>\n
\n\tOracle \u662f\u4e00\u4e2a\u5185\u5b58\u6d88\u8017\u5927\u6237\uff0c\u5b83\u6d88\u8017\u7684\u5185\u5b58\u53ef\u4ee5\u5206\u6210\u4e24\u90e8\u5206——\u8fdb\u7a0b\u5171\u4eab\u90e8\u5206<\/strong>\u548c\u8fdb\u7a0b\u4e13\u6709\u90e8\u5206<\/strong>\u3002 \u8fd9\u91cc\u7684\u8fdb\u7a0b\u4e13\u6307Oracle \u8fdb\u7a0b\uff08Server Process \u548cBackground Process\uff09\uff0c\u8fdb\u7a0b\u5171\u4eab\u90e8\u5206\u5c31\u53eb\u505a SGA <\/strong>\uff08Shared Global Area \uff09\uff0c\u8fdb\u7a0b\u4e13\u6709\u90e8\u5206\u5c31\u53eb\u505a PGA <\/strong>\uff08Program Global Area\uff09\u3002\n<\/p>\n \n\t\u5bf9\u4e8e\u4e0d\u540c\u7c7b\u578b\u7684\u5e94\u7528\u7cfb\u7edf\uff0c\u8fd9\u4e24\u4e2a\u90e8\u5206\u7684\u610f\u4e49\u4e5f\u4e0d\u540c\u3002\u5bf9\u4e8eOLTP\u7cfb\u7edf\uff0c\u5176\u7279\u5f81\u5927\u91cf\u7684\u5c0f\u4e8b\u52a1\uff0c SGA \u8981\u6bd4PGA\u66f4\u4e3a\u91cd\u8981\u3002\u5bf9\u4e8eOLAP \u7cfb\u7edf\u6765\u8bf4\uff0c\u5176\u7279\u5f81\u662f\u5927\u6570\u636e\u91cf\u7684\u5173\u8054\uff0c\u56e0\u6b64PGA \u8981\u6bd4SGA \u5bf9\u7cfb\u7edf\u7684\u5f71\u54cd\u66f4\u5927\u3002\u56e0\u4e3aPGA \u76f4\u63a5\u51b3\u5b9a\u4e86\u5927\u7684\u6392\u5e8f\u3001\u54c8\u5e0c\u64cd\u4f5c\u6548\u7387\u3002\n<\/p>\n \n\t1.SGA\n<\/p>\n \n\tSGA \u662f\u4e00\u5927\u5757\u5185\u5b58\u7684\u603b\u79f0\uff0c\u5176\u5185\u90e8\u5206\u6210\u82e5\u5e72\u7ec4\u6210\u90e8\u5206,\u6bcf\u4e2a\u90e8\u5206\u90fd\u6709\u72ec\u7279\u7684\u4f5c\u7528\u3002\n<\/p>\n \n\t2\uff0eData Buffer Cache\n<\/p>\n \n\t\u7531Server Process \u4ece\u78c1\u76d8\u8bfb\u5165\u7684\u6570\u636e\u5c31\u653e\u5728\u8fd9\u5757\u5185\u5b58\u4e2d\u3002\u800c\u4fee\u6539\u6570\u636e\u65f6\uff0c\u4e5f\u662f\u5728\u8fd9\u4e2a\u533a\u57df\u4e2d\u5bf9\u6570 \u636e\u8fdb\u884c\u4fee\u6539\u3002Data Buffer Cache \u4e2d\u4f1a\u540c\u65f6\u4fdd\u7559\u6570\u636e\u5e93\u88ab\u4fee\u6539\u524d\uff08Before Image\uff0c\u524d\u955c\u50cf\uff09\u548c\u88ab\u4fee\u6539\u540e \uff08After Image \uff0c\u540e\u955c\u50cf\uff09\u7684\u62f7\u8d1d\u3002\n<\/p>\n \n\tData Buffer Cache \u4e2d\u7684\u5185\u5b58\u53ef\u4ee5\u88ab\u5206\u6210 3 \u7c7b:\n<\/p>\n \n\t\u5f53\u7528\u6237\u8fdb\u7a0b\u8bf7\u6c42\u6570\u636e\u65f6\uff0cOracle \u9996\u5148\u67e5\u770b\u6570\u636e\u662f\u5426\u5df2\u7ecf\u5728 Data Buffer Cache \u4e2d\uff0c\u5982\u679c\u6570\u636e\u5df2\u5728 Data Buffer Cache \u4e2d\uff0c\u5219 Server Process\u4e0d\u5fc5\u518d\u8bbf\u95ee\u78c1\u76d8\uff0c\u76f4\u63a5\u4ece SGA \u4e2d\u8bfb\u53d6\u6570\u636e\u5c31\u53ef\u4ee5\u4e86\u3002\u5982\u679c \u6570\u636e\u8fd8\u6ca1\u6709\u52a0\u8f7d\u5230SGA \uff0cServer Process\u5c31\u5fc5\u987b\u4ece\u78c1\u76d8\u8bfb\u5165\u6570\u636e\uff0c\u4f46\u662f\u5728\u8bfb\u5165\u4e4b\u524d\uff0cServer Process \u5fc5\u987b\u4fdd\u8bc1Data Buffer Cache \u4e2d\u6709\u8db3\u591f\u7684 Free Buffer \u6765\u5bb9\u7eb3\u8fd9\u4e9b\u6570\u636e\uff0c\u5982\u679cServer Process\u5728\u626b\u63cf\u4e00 \u5b9a\u6570\u91cf\u7684Buffer \u540e\u8fd8\u6ca1\u6709\u627e\u5230Free Buffer \uff0c\u5b83\u5c31\u4f1a\u901a\u77e5DBWn \u8fdb\u7a0b\u628aDirty Buffer\u5199\u5230\u78c1\u76d8\u4e0a\uff0c\u4e00 \u65e6\u4e9b\u5b8c\u6210\uff0c\u539f\u5148\u8fd9\u4e9bDirty Buffer \u5c31\u53d8\u6210 Free Buffer \uff0c\u5c31\u53ef\u4ee5\u91cd\u7528\u4e86\u3002\n<\/p>\n \n\t\u7a76\u7adf\u628a\u54ea\u4e9b\u4e2aDirty Buffer \u5199\u5230\u78c1\u76d8\uff1f\u8fd9\u5c31\u4f1a\u7528\u5230LRU\uff08Least Recently Used\uff09\u7b97\u6cd5\u4e86\uff0c\u8fd9\u79cd\u7b97 \u6cd5\u786e\u4fdd\u6700\u8fd1\u8d8a\u5c11\u88ab\u4f7f\u7528\u7684\u6570\u636e\u5757\uff0c\u8d8a\u5148\u88ab\u5199\u5230\u78c1\u76d8\uff0c\u7a7a\u95f4\u8d8a\u5148\u88ab\u91ca\u653e\u3002\u8fd9\u79cd\u7b97\u6cd5\u662f\u57fa\u4e8e\u8fd9\u6837\u4e00\u4e2a\u5047 \u8bbe\uff1a“\u8d8a\u8fd1\u88ab\u7528\u5230\u7684\u6570\u636e\uff0c\u5c31\u8d8a\u6709\u53ef\u80fd\u88ab\u518d\u6b21\u7528\u5230”\u3002\u5728 Data Buffer Cache \u4e2d\uff0c\u4e0d\u4ec5\u6709\u4e00\u4e2a LRU List \u5b58\u5728\uff0c\u800c\u662f\u540c\u65f6\u4f7f\u7528\u591a\u4e2a LRU List \uff0c\u5982 Free Buffer \u3001Dirty Buffer \u3001Pinned Buffer \u90fd\u662f\u4f7f\u7528LRU\u7b97\u6cd5\u3002\n<\/p>\n \n\t\uff081\uff09\u6309\u7167\u7528\u9014\u4e0d\u540c\u7684\u591a\u4e2a Buffer Cache\u3002<\/strong>\n<\/p>\n \n\t\u5927\u90e8\u5206\u60c5\u51b5\u4e0b\u6570\u636e\u5e93\u6709\u4e00\u4e2a\u7f3a\u7701\u7684Buffer Cache\u653e\u7f6e\u6240\u6709\u7684\u6570\u636e\u5c31\u8db3\u591f\u4e86\uff0c\u4e0d\u8fc7 Oracle \u5141\u8bb8\u901a \u8fc7\u591a\u4e2aBuffer Cache\u8fdb\u884c\u5fae\u8c03\u3002\n<\/p>\n \n\t\u6570\u636e\u5e93\u4e2d\u7684\u4e0d\u540c\u6570\u636e\u7684\u8bbf\u95ee\u9891\u7387\u662f\u4e0d\u4e00\u6837\u7684\uff0c\u50cf\u7528\u6237\u5c5e\u6027\u3001\u5546\u54c1\u5217\u8868\u8fd9\u79cd\u5b57\u5178\u578b\u6570\u636e\u53ef\u80fd\u9700\u8981 \u7ecf\u5e38\u4f7f\u7528\uff0c\u56e0\u6b64\u8fd9\u7c7b\u6570\u636e\u5e94\u8be5\u5c3d\u53ef\u80fd\u4e45\u7684\u653e\u5728 Buffer Cache\u4e2d\uff0c\u800c\u4e00\u4e9b\u65e5\u5fd7\u578b\u6570\u636e\u53ea\u4f1a\u5076\u5c14\u91c7\u7528\u5230\uff0c \u8fd9\u7c7b\u6570\u636e\u5c31\u5e94\u8be5\u5c3d\u5feb\u5730\u4eceBuffer Cache\u4e2d\u79fb\u8d70\uff0c\u4ee5\u91ca\u653e\u7a7a\u95f4\u3002\u5bf9\u4e8e\u7b26\u5408\u8fd9\u79cd\u7279\u70b9\u7684\u5e94\u7528\u6765\u8bf4\uff0cOracle \u63d0\u4f9b\u4e86\u5176\u4ed6\u4e24\u79cdBuffer Cache——Keep Buffer Pool\u548cRecycle Buffer Pool\uff0c\u518d\u52a0\u4e0a\u7f3a\u7701\u7684 Buffer Cache \u5c31\u67093 \u79cdBuffer Pool \u4e86\u3002\u8fd9 3 \u79cd\u7684\u533a\u522b\u5728\u4e8e\u5bf9\u5176\u4e2d\u6570\u636e\u7684\u4fdd\u7559\u7b56\u7565\uff0cKeep\u5c31\u662f\u4fdd\u7559\u5f97\u5c3d\u91cf\u4e45\uff0c\u800c Recycle\u5c31\u662f\u5c3d\u5feb\u91ca\u653e\uff0c\u5982\u8868\u6240\u793a\u3002\n<\/p>\n \n\t\uff082 \uff09\u6309\u7167\u6570\u636e\u5757\u5927\u5c0f\u7684\u591a\u4e2a Buffer Pool \u3002<\/strong>\n<\/p>\n \n\t\u9664\u4e86\u6309\u7167\u4fdd\u7559\u65f6\u95f4\u5212\u5206Buffer Cache\uff0cOracle \u8fd8\u53ef\u4ee5\u6309\u7167\u6570\u636e\u5757\u7684\u5927\u5c0f\u5206\u914d\u591a\u4e2a Buffer Cache\u3002 Oracle 10g \u4e2d\u5141\u8bb8\u521b\u5efa\u4e0d\u540c\u6570\u636e\u5757\u5927\u5c0f\u7684\u8868\u7a7a\u95f4\uff0cDBA \u5728\u521b\u5efa\u6570\u636e\u5e93\u65f6\u9700\u8981\u4f7f\u7528\u7684 DB_BLOCK_SIZE \u53c2\u6570\uff0c\u8fd9\u4e2a\u53c2\u6570\u51b3\u5b9a\u7684\u662f\u6570\u636e\u5e93\u6807\u51c6\u6570\u636e\u5757\u5927\u5c0f\uff0c\u4ee5\u540e\u521b\u5efa\u7684\u8868\u7a7a\u95f4\u7f3a\u7701\u4f1a\u7ee7\u627f \u8fd9\u4e2a\u5757\u5927\u5c0f\u3002\u4f46\u662fDBA\u4e5f\u53ef\u4ee5\u7528\u5176\u4ed6\u6570\u636e\u5757\u5927\u5c0f\u521b\u5efa\u8868\u7a7a\u95f4\uff0c\u6700\u591a\u53ef\u4ee5\u4f7f\u75285 \u79cd\u4e0d\u540c\u6570\u636e\u5757\u5927\u5c0f \uff082KB \u30014KB \u30018KB \u300116KB\u300132KB\uff09\uff0c\u8fd9\u4e9b\u8868\u7a7a\u95f4\u53eb\u505a\u975e\u6807\u51c6\u6570\u636e\u5757\u5927\u5c0f\u7684\u8868\u7a7a\u95f4\u3002\u8981\u60f3\u5728\u4e00\u4e2a\u6570\u636e \u5e93\u5185\u540c\u65f6\u4f7f\u7528\u591a\u79cd\u6570\u636e\u5757\u5927\u5c0f\uff0c\u4e00\u4e2a\u91cd\u8981\u7684\u6761\u4ef6\u5c31\u662f\u5fc5\u987b\u8981\u914d\u7f6e\u5bf9\u5e94\u7684\u975e\u6807\u51c6Buffer Cache\u3002\u5bf9\u5e94 \u53c2\u6570\u662fDB_nK_CACHE_SIZE\u3002\n<\/p>\n \n\t\u4e4b\u524d\u63d0\u5230\u7684Keep Buffer Pool\u3001Recycle Buffer Pool\u90fd\u53ea\u7528\u4e8e\u6807\u51c6\u6570\u636e\u5757\u3002\u800cDefault Buffer Pool \u5219\u662f\u7531\u6240\u6709\u7684\u6807\u51c6\u548c\u975e\u6807\u51c6Buffer Pool \u7ec4\u548c\u5728\u4e00\u8d77\u7684\u3002\u6240\u8c13\u6807\u51c6\u3001\u975e\u6807\u51c6\u662f\u6839\u636e\u521b\u5efa\u6570\u636e\u5e93\u65f6\u6307\u5b9a \u7684DB_BLOCK_SIZE \u800c\u8a00\u7684\uff0c\u5982\u679c\u8fd9\u4e2a\u503c\u662f2KB \uff0c\u90a3\u4e48\u5176\u4ed6\u76844KB \u30018KB \u300116KB\u300132KB \u5c31\u53eb\u505a \u975e\u6807\u51c6\u6570\u636e\u5757\u3002\u5982\u679c\u5b9a\u4e49\u6210 32KB\uff0c\u90a3\u4e48 2KB \u30014KB \u30018KB \u300116KB \u5c31\u53eb\u505a\u975e\u6807\u51c6\u6570\u636e\u5757\u3002\n<\/p>\n \n\tShared Pool\u662fSGA \u4e2d\u53e6\u4e00\u4e2a\u975e\u5e38\u91cd\u8981\u7684\u533a\u57df\uff0c\u5c24\u5176\u5bf9\u4e8eOLTP\u7cfb\u7edf\u6765\u8bf4\uff0cShared Pool\u914d\u7f6e\u5bf9 \u4e8e\u7cfb\u7edf\u6027\u80fd\u7684\u610f\u4e49\u5c24\u4e3a\u91cd\u8981\u3002\u548c Data Buffer Cache \u5b58\u653e\u7684\u662f\u7528\u6237\u6570\u636e\u4e0d\u540c\uff0cShared Pool \u4e2d\u5b58\u653e\u7684\u662f \u4ee3\u7801\uff0c\u5305\u62ecPL\/SQL \u4ee3\u7801\u3001SQL \u8bed\u53e5\u4ee5\u53ca\u6570\u636e\u5b57\u5178\u4fe1\u606f\u3002Shared Pool\u53c8\u53ef\u4ee5\u5206\u6210 Library Cache<\/strong> \u548c Dictionary Cache<\/strong>\u4e24\u4e2a\u533a\u57df\u3002\n<\/p>\n \n\t\u5982\u679c\u7528\u6237\u6709\u8fc7\u5176\u4ed6\u8bed\u8a00\u7684\u5f00\u53d1\u7ecf\u9a8c\uff0c\u4e00\u5b9a\u77e5\u9053\u7f16\u8bd1\u8fc7\u7a0b\uff0c\u4e5f\u5c31\u662f\u8981\u628a\u7528\u6237\u4ee3\u7801\u8f6c\u6362\u6210\u673a\u5668\u8bed\u8a00\uff0c\u6bd4\u5982Java \u8bed\u8a00\u8981\u628a*.java \u6587\u4ef6\u7f16\u8bd1\u6210.class \u6587\u4ef6\u3002\u6570\u636e\u5e93\u4e5f\u662f\u4e00\u6837\uff0c\u7528\u6237\u63d0\u4ea4\u7684\u65e0\u8bba\u662f\u7528 PL\/SQL \u7f16 \u5199\u7684\u5b58\u50a8\u8fc7\u7a0b\u6216\u8005\u7eaf\u7cb9\u7684SQL \u4ee3\u7801\uff0c\u8fd9\u4e9b\u4ee3\u7801\u90fd\u662f\u57fa\u4e8e\u4eba\u7c7b\u8bed\u8a00\u7f16\u5199\u7684\uff0c\u8981\u60f3\u8ba1\u7b97\u673a\u80fd\u591f\u6267\u884c\u8fd9\u4e9b \u4ee3\u7801\uff0c\u9996\u5148\u8981\u628a\u5b83\u4eec\u7f16\u8bd1\u6210 CPU \u53ef\u8bc6\u522b\u7684\u673a\u5668\u4ee3\u7801\uff0c\u8fd9\u4e2a\u8fc7\u7a0b\u5c31\u662f\u7f16\u8bd1\u3002\u800c\u7f16\u8bd1\u4ea7\u751f\u7684\u673a\u5668\u4ee3\u7801\u5c31 \u4fdd\u5b58\u5728Library Cache \u4e2d\uff0cShared Pool \u662f\u4e00\u4e2a\u6240\u6709\u7528\u6237\u53ef\u4ee5\u5171\u4eab\u7684\u533a\u57df\uff0c\u8fd9\u6837\u5c31\u53ef\u4ee5\u83b7\u5f97\u4e24\u4e2a\u597d\u5904\uff1a \u9996\u5148\uff0c\u7528\u6237\u5982\u679c\u518d\u6b21\u6267\u884c\u540c\u4e00\u6bb5\u4ee3\u7801\u65f6\uff0c\u5c31\u53ef\u4ee5\u7701\u6389\u89e3\u6790\u8fc7\u7a0b\uff0c\u76f4\u63a5\u91cd\u7528\u5148\u524d\u751f\u6210\u7684\u673a\u5668\u4ee3\u7801\uff1b\u5176 \u6b21\uff0c\u5982\u679c\u5176\u4ed6\u7528\u6237\u6267\u884c\u76f8\u540c\u4ee3\u7801\uff0c\u4e5f\u80fd\u591f\u91cd\u7528\uff0c\u51cf\u5c11\u89e3\u6790\u3002\n<\/p>\n \n\t\u4e00\u4e2aSQL \u8bed\u53e5\u5b8c\u6574\u6267\u884c\u8fc7\u7a0b\u53ef\u4ee5\u5206\u6210 4 \u4e2a\u9636\u6bb5:\n<\/p>\n \n\t\uff081\uff09 \u89e3\u6790\u3002 <\/strong> \n\t\u8fd9\u4e9b\u68c0\u67e5\u901a\u8fc7\u540e\uff0c\u518d\u68c0\u67e5\u8fd9\u4e2a\u8bed\u53e5\u4e4b\u524d\u662f\u5426\u5df2\u7ecf\u89e3\u6790\u8fc7\u4e86\u3002Oracle \u5bf9\u6bcf\u4e2a\u8bed\u53e5\u90fd\u4f1a\u8ba1\u7b97\u51fa\u54c8\u5e0c \u503c\uff0c\u7528\u8fd9\u4e2a\u503c\u5728Shared Pool \u4e2d\u67e5\u770b\u662f\u5426\u6709\u5bf9\u5e94\u7684\u6267\u884c\u8ba1\u5212\u3002\u5982\u679c\u6709\uff0c\u5c31\u8bf4\u660e\u8fd9\u4e2a\u8bed\u53e5\u66fe\u7ecf\u6267\u884c\u8fc7\uff0c \u5df2\u6709\u7684\u6267\u884c\u8ba1\u5212\u62ff\u8fc7\u6765\u5c31\u53ef\u4ee5\u4f7f\u7528\uff0c\u800c\u4e0d\u518d\u9700\u8981\u6267\u884c\u4e0b\u9762\u7684\uff082 \uff09\u3001\uff083\uff09\u6b65\uff08\u8fd9\u4e5f\u5c31\u662f\u53ea\u8fdb\u884c\u8f6f\u89e3\u6790<\/strong> Soft Parse\uff09\uff1b\u5982\u679c\u6ca1\u6709\uff0c\u5219\u5fc5\u987b\uff081 \uff09\u3001\uff082 \uff09\u3001\uff083 \uff09\u6b65\u90fd\u6267\u884c\u5b8c\u540e\u624d\u80fd\u4ea7\u751f\u6267\u884c\u8ba1\u5212\uff08\u4e5f\u5c31\u662f\u6240\u8c13\u7684 Hard Parse\uff09\u3002\n<\/p>\n \n\t\uff082 \uff09\u4f18\u5316\u3002<\/strong>\n<\/p>\n \n\t\u8fd9\u4e2a\u9636\u6bb5\u6839\u636e\u5bf9\u8c61\u7684\u7edf\u8ba1\u4fe1\u606f\u3001\u5f53\u524d\u9009\u62e9\u7684\u4f18\u5316\u5668\u6a21\u5f0f\uff08CBO\/RBO\uff09\u6765\u786e\u5b9a\u6700\u4f73\u8bbf\u95ee\u8def\u5f84\u3002\u6240 \u8c13\u5bf9\u8c61\u7684\u7edf\u8ba1\u4fe1\u606f\uff0c\u6bd4\u5982\u4e00\u4e2a\u8868\u91cc\u9762\u6709\u591a\u5c11\u6761\u8bb0\u5f55\u3001\u6bcf\u6761\u8bb0\u5f55\u5e73\u5747\u957f\u5ea6\u3001\u5360\u636e\u591a\u5c11\u4e2a\u6570\u636e\u5757\u3001\u7d22\u5f15 \u7684\u9ad8\u5ea6\u7b49\u3002\u8fd9\u4e9b\u4fe1\u606f\u8bb0\u5f55\u5728\u7cfb\u7edf\u5b57\u5178\u4e2d\uff0c\u6bd4\u5982user_tables.num_rows \u3002\n<\/p>\n \n\t\u53e6\u5916\u4e00\u4e2a\u5f71\u54cd\u4f18\u5316\u7684\u56e0\u7d20\u662f“\u4f18\u5316\u5668\u6a21\u5f0f”\uff08Optimizer Mode \uff09\u3002\u8fd9\u4e2a\u914d\u7f6e\u662f\u544a\u8bc9 Oracle \u5e0c\u671b\u5982 \u4f55\u8fd4\u56de\u8bb0\u5f55\uff0c\u6bd4\u5982 first_rows_n\u4ee3\u8868\u5c3d\u5feb\u8fd4\u56de\u5934 n \u6761\u8bb0\u5f55\uff1ball_rows \u4ee3\u8868\u7740\u5c3d\u5feb\u8fd4\u56de\u6574\u4e2a\u8bb0\u5f55\u96c6\uff0c\u800c \u4e0d\u5173\u5fc3\u5934\u51e0\u6761\u7684\u8fd4\u56de\u901f\u5ea6\u3002\u6a21\u5f0f\u4e0d\u540c\u4f1a\u4ea7\u751f\u4e0d\u540c\u7684\u6267\u884c\u8ba1\u5212\u3002\n<\/p>\n \n\t\u6839\u636e\u8fd9\u4e24\u7c7b\u4fe1\u606f\uff0cOracle \u7684\u4f18\u5316\u8d77\u5f15\u64ce\u4f1a\u4ea7\u751f\u591a\u4e2a\u8bbf\u95ee\u8def\u5f84\uff0c\u5982\u5168\u8868\u626b\u63cf\u3001\u7d22\u5f15\u626b\u63cf\u3001Nest Loop Join \u6216Hash Join \u7b49\uff0cOracle \u4f1a\u8ba1\u7b97\u6bcf\u79cd\u8bbf\u95ee\u8def\u5f84\u7684\u6210\u672c\uff0c\u628a\u6210\u672c\u6700\u5c0f\u7684\u8bbf\u95ee\u8def\u5f84\u4f5c\u4e3a\u6700\u4f73\u8def\u5f84\u3002\n<\/p>\n \n\t\uff083 \uff09\u4ea7\u751f\u6267\u884c\u8ba1\u5212\u3002<\/strong>\n<\/p>\n \n\t\u8fd9\u4e00\u9636\u6bb5\u6839\u636e\u4e0a\u4e00\u9636\u6bb5\u4ea7\u751f\u7684\u6700\u5c0f\u6210\u672c\u7684\u8bbf\u95ee\u8def\u5f84\uff0c\u751f\u6210\u6700\u7ec8\u7684\u6267\u884c\u8ba1\u5212\u3002\n<\/p>\n \n\t\uff084 \uff09\u8fd4\u56de\u67e5\u8be2\u7ed3\u679c\u3002<\/strong>\n<\/p>\n \n\t\u4f9d\u636e\u4e0a\u4e00\u6b65\u7684\u6267\u884c\u8ba1\u5212\uff0c\u8bbf\u95ee\u6570\u636e\u83b7\u5f97\u7ed3\u679c\u96c6\uff0c\u8fd4\u56de\u7ed9\u7528\u6237\u3002\u5982\u679c\u662fDML\u8bed\u53e5\uff0c\u800c\u4fee\u6539\u6570\u636e \u5e76\u8fd4\u56de\u7ed3\u679c\u3002 \n\tLibrary Cache \u4e2d\u5b58\u653e\u7684\u4ee3\u7801\u90e8\u5206\uff0cDictionary Cache\u4e2d\u5b58\u653e\u7684\u6570\u636e\u5b57\u5178\u4fe1\u606f<\/strong>\u3002\u5728\u89e3\u6790\u9636\u6bb5\uff0c\u89e3\u6790 \u5668\u8981\u5224\u6bb5\u8868\u540d\u3001\u5217\u540d\u662f\u5426\u6b63\u786e\u3001\u7528\u6237\u662f\u5426\u6709\u6743\u9650\u6267\u884c\u8bf7\u6c42\u7684\u64cd\u4f5c\uff0c\u8fd9\u4e9b\u4fe1\u606f\u5c31\u662f\u6570\u636e\u5b57\u5178\uff0c\u5305\u62ec\u5728 \u63a5\u4e0b\u6765\u7684\u4f18\u5316\u9636\u6bb5\uff0cCBO\u751f\u6210\u6267\u884c\u8ba1\u5212\u6240\u7528\u5230\u7684\u5bf9\u8c61\u7edf\u8ba1\u6570\u636e\u90fd\u6765\u81ea\u4e8e\u6570\u636e\u5b57\u5178\u3002\u5982\u679c\u8fd9\u4e9b\u6570\u636e\u4e0d \u5728\u5185\u5b58\u4e2d\uff0cOracle \u5c31\u9700\u8981\u4ece\u6570\u636e\u5b57\u5178\u628a\u8fd9\u4e9b\u6570\u636e\u8bfb\u5165 Dictionary Cache\u3002\u6570\u636e\u5b57\u5178\u5728 Dictionary Cache \u7f13\u5b58\u7684\u8d8a\u591a\u3001\u4fdd\u7559\u65f6\u95f4\u8d8a\u957f\uff0c\u89e3\u6790\u65f6\u95f4\u8d8a\u77ed\uff0c\u7cfb\u7edf\u6027\u80fd\u8d8a\u597d\u3002\n<\/p>\n \n\tRedo Log Buffer \u4f7f\u7528\u6765\u4fdd\u5b58Redo \u8bb0\u5f55\uff0c\u548c Buffer Cahce\u3001Shared Pool \u6bd4\u8d77\u6765\uff0c\u8fd9\u4e2a\u533a\u57df\u7a7a\u95f4 \u975e\u5e38\u5c0f\uff0c\u901a\u5e38\u53ea\u6709\u51e0MB\u3002\u5f53\u4e00\u4e2aServer Process \u6539\u53d8 Data Buffer Cache \u4e2d\u7684\u6570\u636e\u65f6\uff08DML\u64cd\u4f5c\uff09\uff0c \u5c31\u4f1a\u4ea7\u751fRedo\u8bb0\u5f55\uff0c\u8fd9\u4e9b\u8bb0\u5f55\u4fdd\u5b58\u5728 Redo Log Buffer \u4e2d\u3002LGWR \u8fdb\u7a0b\u8d1f\u8d23\u628aRedo Log Buffer \u4e2d\u7684 \u5185\u5bb9\u5199\u5230\u78c1\u76d8\u4e0a\u7684Redo Log File \u4e2d\u3002\n<\/p>\n \n\tRedo Log Buffer\u662f\u91c7\u7528\u5faa\u73af\u65b9\u5f0f\u5de5\u4f5c\u7684\uff0c\u4e00\u65e6LGWR \u8fdb\u7a0b\u628a\u65e5\u5fd7\u5185\u5bb9\u5199\u5230\u78c1\u76d8\uff0cLGWR \u5c31\u53ef \u4ee5\u8986\u76d6\u8fd9\u5757\u5185\u5bb9\u3002LGWR \u901a\u5e38\u662f\u7cfb\u7edf\u4e2d\u6700\u7e41\u5fd9\u7684\u8fdb\u7a0b\uff0cOracle \u63d0\u4f9b\u4e86\u4e00\u79cd Nologging\u6280\u672f\u53ef\u4ee5\u8df3\u8fc7 Redo Log\u751f\u6210\uff0c\u4ece\u800c\u51cf\u5c11 LGWR \u7684\u8d1f\u8f7d\uff0c\u4e0d\u8fc7\u8fd9\u4e2a\u6280\u672f\u53ea\u662f\u5728\u6709\u9650\u7684\u51e0\u79cd\u573a\u5408\u6709\u7528\uff0c\u6bd4\u5982\u76f4\u63a5\u6570 \u636e\u52a0\u8f7d\u3002\n<\/p>\n \n\t\u8fd9\u51e0\u4e2a\u5185\u5b58\u7ec4\u4ef6\u76f8\u5bf9\u6765\u8bf4\u5c31\u4e0d\u662f\u5f88\u91cd\u8981\u4e86\uff0cLarge Pool \u6700\u4e3b\u8981\u7684\u7528\u9014\u5c31\u662f\u4f9b RMAN \u5907\u4efd\u548c\u5171\u4eab \u8fde\u63a5\u6a21\u5f0f\u3002Java Pool \u7528\u4e8e\u652f\u6301 Java \u865a\u62df\u673a\uff08JVM \uff09\uff0cStream Pool \u7528\u4e8e\u652f\u6301\u6d41\u3002\n<\/p>\n \n\t\u5728Oracle 10g\u4e4b\u524d\u7684\u7248\u672c\u4e2d\uff0cSGA \u5404\u4e2a\u7ec4\u4ef6\u7684\u8c03\u6574\u4e5f\u662f DBA\u7684\u65e5\u5e38\u5de5\u4f5c\u4e4b\u4e00\u3002\u4ece Oracle 10g\u5f00 \u59cb\uff0c\u8fd9\u4e2a\u533a\u57df\u80fd\u591f\u81ea\u52a8\u8c03\u6574\u4e86\uff0c\u8fd9\u4e2a\u7279\u6027\u662fOracle \u81ea\u52a8\u7ba1\u7406\u529f\u80fd\u7684\u4e00\u90e8\u5206\uff0c\u7528\u6237\u53ea\u9700\u8981\u8bbe\u7f6e\u4e00\u4e2a\u65b0\u589e \u7684\u53c2\u6570 SGA_TARGET\u5c31\u53ef\u4ee5\u5b9e\u73b0 SGA \u7684\u81ea\u52a8\u8c03\u6574\u3002SGA \u81ea\u52a8\u8c03\u6574\u89c1\u540e\u9762\u7ae0\u8282\u3002\n<\/p>\n \n\t\u5bf9\u4e8e\u6bcf\u4e2a\u670d\u52a1\u8fdb\u7a0b\u3001\u540e\u53f0\u8fdb\u7a0b\uff0cOracle \u90fd\u4f1a\u4e3a\u5176\u5206\u914d\u4e00\u4e2a PGA \uff0c\u8fd9\u5757\u5185\u5b58\u533a\u57df\u7528\u4e8e\u4fdd\u5b58\u6bcf\u4e2a\u7528 \u6237\u7684\u79c1\u6709\u6570\u636e\u3002\u548cSGA \u7684\u5171\u4eab\u4e0d\u540c\uff0cPGA \u662f\u6392\u4ed6\u4f7f\u7528\u7684\u3002PGA \u53ef\u4ee5\u5206\u6210\u4e24\u90e8\u5206\u3002\n<\/p>\n \n\t\t\tPrivate SQL Area<\/strong>\uff1a\u8fd9\u5757\u533a\u57df\u7528\u4e8e\u4fdd\u5b58 SQL \u7ed1\u5b9a\u53d8\u91cf\u4fe1\u606f\uff0c\u867d\u7136 SQL \u8bed\u53e5\u7684\u6267\u884c\u8ba1\u5212\u53ef\u4ee5 \u5171\u4eab\uff0c\u4f46\u662f\u6bcf\u4e2a\u7528\u6237\u7684\u7ed1\u5b9a\u53d8\u91cf\u4fe1\u606f\u5374\u8981\u4fdd\u5b58\u5728 PGA \u4e2d\uff1bOPEN_CRUSRO \u5b9a\u4e49\u7684\u5c31\u662f\u5728 \u8fd9\u5757\u533a\u57df\u4e2d\uff0c\u7528\u6237\u4fdd\u7559\u7684 Cursor \u6570\u91cf\u3002\n\t\t<\/p>\n<\/li>\n \n\t\t\tRuntime Area<\/strong>\uff1a\u6bcf\u5f53 Session \u6267\u884c\u4e00\u4e2a\u8bed\u53e5\u65f6\u5206\u914d\u7684\u7a7a\u95f4\uff0c\u8fd9\u5757\u7a7a\u95f4\u53ef\u4ee5\u7528\u4e8e\u6570\u636e\u6392\u5e8f\u3001 Hash\u3001\u8fde\u63a5\u7b49\uff0c\u5f53\u8bed\u53e5\u6267\u884c\u5b8c\u6bd5\u540e\uff0c\u8fd9\u5757\u533a\u57df\u5c31\u88ab Oracle \u91ca\u653e\u4e86\u3002\n\t\t<\/p>\n<\/li>\n<\/ul>\n \n\t\u4e3a\u4e86\u51cf\u5c11\u7528\u6237\u7b49\u5f85\u65f6\u95f4\uff0c\u52a0\u5feb\u54cd\u5e94\u901f\u5ea6\uff0cOracle \u4f1a\u5c3d\u91cf\u5728\u5185\u5b58\u4e2d\u5b8c\u6210\u6392\u5e8f\u3001Hash\u3001\u8fde\u63a5\u7b49\u64cd\u4f5c\uff0c \u8fd9\u5757\u5185\u5b58\u5c31\u662fPGA \u7684Runtime Area \u4e2d\u3002\u5982\u679c\u64cd\u4f5c\u80fd\u591f\u5728\u5185\u5b58\u4e2d\u5b8c\u6210\uff0c\u4e0d\u9700\u8981\u78c1\u76d8IO\uff0c\u8fd9\u79cd\u64cd\u4f5c\u5c31 \u53eb\u505aOptimal Mode Operation\u3002\u5426\u5219\uff0c\u5982\u679c\u4e0d\u80fd\u5728\u5185\u5b58\u4e2d\u5b8c\u6210\uff0c\u5c31\u4f1a\u628a\u90e8\u5206\u4e2d\u95f4\u6570\u636e\u5148\u8f6c\u79fb\u5230\u78c1\u76d8\u4e0a\uff0c \u8fd9\u79cd\u64cd\u4f5c\u5c31\u53eb\u505aOne\uff08Multiple\uff09-Pass\uff08\u4e00\u8def\u6216\u591a\u8def\uff09Operation\u3002\u78c1\u76d8\u64cd\u4f5c\u4f1a\u964d\u4f4e\u7cfb\u7edf\u6027\u80fd\u3002\u56e0\u6b64 PGA \u5927\u5c0f\u548c\u6027\u80fd\u6709\u5bc6\u5207\u5173\u7cfb\u3002\u8fd9\u4e9b\u5185\u5b58\u533a\u57df\u901a\u8fc7 SORT_AREA_SIZE\u3001HASH_AREA_SIZE\u3001 BITMAP_AREA_SIZE \u5b9a\u4e49\u3002\n<\/p>\n \n\tOracle 9i \u5f00\u59cb\u5f15\u5165\u4e86 PGA \u7684\u81ea\u52a8\u7ba1\u7406\uff0c\u901a\u8fc7\u628aWORKAREA_SIZE_POLICY\u8bbe\u7f6e\u4e3aAUTO \u6765 \u542f\u7528PGA \u81ea\u52a8\u7ba1\u7406\uff0c\u5982\u679c\u8fd9\u4e2a\u53c2\u6570\u8bbe\u7f6e\u6210 MANUAL\uff0c\u5c31\u9000\u56de\u5230\u624b\u52a8\u7ba1\u7406\u3002\u81ea\u52a8\u7ba1\u7406\u53ea\u9700\u8981\u5b9a\u4e49\u4e00 \u4e2a\u53c2\u6570PGA_AGGREGATE_TRAGET \u5c31\u597d\u4e86\u3002PGA \u81ea\u52a8\u7ba1\u7406\u5bf9\u4e8e\u5185\u5b58\u4f7f\u7528\u6548\u7387\u66f4\u9ad8\uff0c\u6bd4\u5982\u5982\u679c\u4f7f \u7528\u624b\u52a8\u7ba1\u7406\uff0c\u90a3\u4e48\u6bcf\u4e2a\u4f1a\u8bdd\u5206\u914d\u7684 PGA \u4e0d\u4f1a\u81ea\u52a8\u5f52\u8fd8\u7ed9\u7cfb\u7edf\uff0c\u65e0\u8bba\u4f1a\u8bdd\u662f\u5426\u6267\u884c\u64cd\u4f5c\u8fd8\u662f IDLE \u72b6 \u6001\uff0c\u90fd\u5fc5\u987b\u5728\u7528\u6237\u9000\u51fa\u540e\uff08Log Off\uff09PGA \u7a7a\u95f4\u624d\u4f1a\u5f52\u8fd8\u7ed9\u7cfb\u7edf\uff0c\u8fd9\u5c31\u53ef\u80fd\u9020\u6210\u5927\u91cf\u5185\u5b58\u88ab\u95f2\u7f6e\uff0c\u800c \u771f\u6b63\u9700\u8981\u5de5\u4f5c\u7684\u4f1a\u8bdd\u6709\u65e0\u6cd5\u83b7\u5f97\u8db3\u591f\u7684PGA \uff0c\u800c\u81ea\u52a8\u7ba1\u7406\u4e2d\uff0c\u4e00\u65e6\u4f1a\u8bdd\u6267\u884c\u7684\u64cd\u4f5c\u7ed3\u675f\uff0c\u4f7f\u7528\u7684 Runtime-Area \u5c31\u4f1a\u81ea\u52a8\u5f52\u8fd8\u7ed9\u64cd\u4f5c\u7cfb\u7edf\u3002\n<\/p>\n \n\t\u8f6c\u8f7d\u81ea\uff1ahttp:\/\/www.sunansheng.com\/2016\/04\/29\/oracle-memory\/<\/p>\n","protected":false},"excerpt":{"rendered":" \u5185\u5b58\u7ed3\u6784 \u73b0\u4ee3\u8ba1\u7b97\u673a\u4e2d\uff0cCPU \u5bf9\u5185\u5b58\u7684\u8bbf\u95ee\u901f\u5ea6\u8981\u6bd4\u4ece\u78c1\u76d8\u7684\u901f\u5ea6\u5feb\u5343\u500d\uff0c\u56e0\u6b64 Oracle \u5bf9\u4e8e\u6570\u636e\u7684\u8bbf\u95ee \u4e5f … \u7ee7\u7eed\u9605\u8bfbOracle \u5185\u5b58\u7ed3\u6784\u8be6\u89e3\uff08\u8f6c\u8f7d\uff09<\/span> \n
\n\n
\n \n\n\t\t\t\tBuffer Pool \u540d\u79f0\n\t\t\t<\/th>\n \n\t\t\t\t\u521d\u59cb\u5316\u53c2\u6570\n\t\t\t<\/th>\n \n\t\t\t\t\u8bf4 \u660e\n\t\t\t<\/th>\n<\/tr>\n<\/thead>\n \n \n\t\t\t\tKeep Buffer Pool\n\t\t\t<\/td>\n \n\t\t\t\tDB_KEEP_CACHE_SIZE\n\t\t\t<\/td>\n \n\t\t\t\t\u8fd9\u4e2a\u533a\u57df\u5185\u7684\u6570\u636e\u4f1a\u5c3d\u53ef\u80fd\u4e45\u5730\u4fdd\u7559\u5728\u5185\u5b58\u4e2d\u3002 \u5bf9\u4e8e\u90a3\u4e9b\u4f53\u79ef\u8f83\u5c0f\u3001\u8bbf\u95ee\u9891\u7e41\u7684\u8868\uff0c\u6bd4\u5982\u7528\u6237\u5c5e \u6027\u8868\uff0c\u53ef\u4ee5\u8003\u8651\u653e\u5728\u8fd9\u4e2aCache \u4e2d\uff0c\u4ee5\u63d0\u9ad8\u8bbf\u95ee \u901f\u5ea6\n\t\t\t<\/td>\n<\/tr>\n \n \n\t\t\t\tRecycle Buffer Pool\n\t\t\t<\/td>\n \n\t\t\t\tDB_RECYCLE_CACHE_SIZE\n\t\t\t<\/td>\n \n\t\t\t\t\u653e\u5728\u8fd9\u4e2a\u533a\u57df\u4e2d\u7684\u6570\u636e\u4e00\u7528\u5b8c\u5c31\u4f1a\u88ab\u79fb\u51fa\u3002\u5bf9\u4e8e \u90a3\u4e9b\u4f53\u79ef\u5de8\u5927\u3001\u5076\u5c14\u4f7f\u7528\u7684\u65e5\u5fd7\u8868\uff0c\u53ef\u4ee5\u8003\u8651\u653e \u5728\u8fd9\u4e2a\u5185\u5b58\u4e2d\uff0c\u4ee5\u5c3d\u5feb\u91ca\u653e\u5185\u5b58\n\t\t\t<\/td>\n<\/tr>\n \n \n\t\t\t\tDefault Buffer Pool\n\t\t\t<\/td>\n \n\t\t\t\tDB_CACHE_SIZE\n\t\t\t<\/td>\n \n\t\t\t\t\u7f3a\u7701\u7684Cache\n\t\t\t<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \n\t3\uff0eShared Pool
\n<\/h3>\n
\n\t\u5728\u8fd9\u4e2a\u9636\u6bb5\uff0c\u8981\u8fdb\u884c\u8bed\u4e49\u3001\u8bed\u6cd5\u5206\u6790\u3001\u6743\u9650\u68c0\u67e5\uff0c\u5305\u62ec\u8bed\u53e5\u662f\u5426\u62fc\u5199\u6b63\u786e\u3001\u662f\u5426\u6709\u8bed\u6cd5\u9519\u8bef\u3001 \u6570\u636e\u5e93\u662f\u5426\u6709a \u8fd9\u4e2a\u5bf9\u8c61\u3001\u7528\u6237\u662f\u5426\u6709 a \u7684\u8bbf\u95ee\u6743\u9650\u7b49\u3002\n<\/p>\n
\n\t\u524d3 \u4e2a\u9636\u6bb5\u662f\u8d44\u6e90\u5bc6\u96c6\u578b\u64cd\u4f5c\uff0c\u5305\u62ec CPU \u3001Latch\u3001Lock\u5404\u79cd\u8d44\u6e90\uff0c\u5bf9\u4e8e\u7cfb\u7edf\u6027\u80fd\u5f71\u54cd\u6bd4\u8f83\u660e \u663e\u3002\u800cShared Pool \u7684\u76ee\u7684\u5c31\u662f\u4e3a\u4e86\u51cf\u5c11\u524d 3 \u4e2a\u9636\u6bb5\u7684\u6d3b\u52a8\u3002\n<\/p>\n\n\t4\uff0eRedo Log Buffer
\n<\/h3>\n\n\t5\uff0eLarge Pool \u3001Java Pool\u3001Stream Pool
\n<\/h3>\n\n\t6\uff0eSGA\u81ea\u52a8\u7ba1\u7406
\n<\/h3>\n\n\tPGA
\n<\/h3>\n\n