TableCache.FindTable() to avoid the mem copy of file number
TableCache.FindTable() to avoid the mem copy of file number

Summary: I'm not sure what's the purpose of encoding file number to a new buffer for looking up the table cache. It seems to be unnecessary to me. With this patch, we point the lookup key to the address of the int64 of the file number.

Test Plan: make all check

Reviewers: dhruba, haobo, igor, kailiu

Reviewed By: dhruba

CC: leveldb

Differential Revision: https://reviews.facebook.net/D14811

luckywhu/rocksdb,flabby/rocksdb,facebook/rocksdb,Applied-Duality/rocksdb,zhangpng/rocksdb,Andymic/rocksdb,makelivedotnet/rocksdb,dkorolev/rocksdb,norton/rocksdb,OverlordQ/rocksdb,NickCis/rocksdb,wat-ze-hex/rocksdb,mbarbon/rocksdb,vashstorm/rocksdb,temicai/rocksdb,Vaisman/rocksdb,lgscofield/rocksdb,JoeWoo/rocksdb,dkorolev/rocksdb,SunguckLee/RocksDB,geraldoandradee/rocksdb,OverlordQ/rocksdb,alihalabyah/rocksdb,vmx/rocksdb,skunkwerks/rocksdb,anagav/rocksdb,rDSN-Projects/rocksdb.replicated,anagav/rocksdb,RyanTech/rocksdb,mbarbon/rocksdb,norton/rocksdb,JohnPJenkins/rocksdb,hobinyoon/rocksdb,sorphi/rocksdb,lgscofield/rocksdb,makelivedotnet/rocksdb,temicai/rocksdb,vmx/rocksdb,kaschaeffer/rocksdb,sorphi/rocksdb,fengshao0907/rocksdb,rDSN-Projects/rocksdb.replicated,temicai/rocksdb,facebook/rocksdb,fengshao0907/rocksdb,Andymic/rocksdb,kaschaeffer/rocksdb,wenduo/rocksdb,tizzybec/rocksdb,JoeWoo/rocksdb,tsheasha/rocksdb,geraldoandradee/rocksdb,JohnPJenkins/rocksdb,OverlordQ/rocksdb,Vaisman/rocksdb,wat-ze-hex/rocksdb,flabby/rocksdb,NickCis/rocksdb,JohnPJenkins/rocksdb,virtdb/rocksdb,biddyweb/rocksdb,wenduo/rocksdb,jalexanderqed/rocksdb,msb-at-yahoo/rocksdb,ylong/rocksdb,ryneli/rocksdb,caijieming-baidu/rocksdb,biddyweb/rocksdb,msb-at-yahoo/rocksdb,mbarbon/rocksdb,flabby/rocksdb,wat-ze-hex/rocksdb,hobinyoon/rocksdb,ylong/rocksdb,tsheasha/rocksdb,sorphi/rocksdb,zhangpng/rocksdb,skunkwerks/rocksdb,temicai/rocksdb,wskplho/rocksdb,wenduo/rocksdb,siddhartharay007/rocksdb,JackLian/rocksdb,tschottdorf/rocksdb,NickCis/rocksdb,IMCG/RcoksDB,Applied-Duality/rocksdb,fengshao0907/rocksdb,ryneli/rocksdb,zhangpng/rocksdb,luckywhu/rocksdb,Applied-Duality/rocksdb,rDSN-Projects/rocksdb.replicated,mbarbon/rocksdb,OverlordQ/rocksdb,vmx/rocksdb,bbiao/rocksdb,wlqGit/rocksdb,jalexanderqed/rocksdb,facebook/rocksdb,alihalabyah/rocksdb,wlqGit/rocksdb,virtdb/rocksdb,JohnPJenkins/rocksdb,bbiao/rocksdb,SunguckLee/RocksDB,bbiao/rocksdb,ryneli/rocksdb,amyvmiwei/rocksdb,JohnPJenkins/rocksdb,Andymic/rocksdb,makelivedotnet/rocksdb,anagav/rocksdb,ylong/rocksdb,sorphi/rocksdb,amyvmiwei/rocksdb,makelivedotnet/rocksdb,wlqGit/rocksdb,SunguckLee/RocksDB,biddyweb/rocksdb,kaschaeffer/rocksdb,biddyweb/rocksdb,temicai/rocksdb,Vaisman/rocksdb,skunkwerks/rocksdb,tizzybec/rocksdb,hobinyoon/rocksdb,makelivedotnet/rocksdb,wat-ze-hex/rocksdb,vashstorm/rocksdb,flabby/rocksdb,anagav/rocksdb,vmx/rocksdb,Vaisman/rocksdb,geraldoandradee/rocksdb,skunkwerks/rocksdb,vashstorm/rocksdb,dkorolev/rocksdb,SunguckLee/RocksDB,wlqGit/rocksdb,hobinyoon/rocksdb,dkorolev/rocksdb,SunguckLee/RocksDB,IMCG/RcoksDB,norton/rocksdb,makelivedotnet/rocksdb,vmx/rocksdb,lgscofield/rocksdb,kaschaeffer/rocksdb,jalexanderqed/rocksdb,lgscofield/rocksdb,wenduo/rocksdb,norton/rocksdb,RyanTech/rocksdb,SunguckLee/RocksDB,JoeWoo/rocksdb,amyvmiwei/rocksdb,amyvmiwei/rocksdb,alihalabyah/rocksdb,JackLian/rocksdb,ylong/rocksdb,norton/rocksdb,virtdb/rocksdb,luckywhu/rocksdb,tschottdorf/rocksdb,sorphi/rocksdb,vashstorm/rocksdb,ylong/rocksdb,geraldoandradee/rocksdb,tizzybec/rocksdb,anagav/rocksdb,norton/rocksdb,IMCG/RcoksDB,luckywhu/rocksdb,alihalabyah/rocksdb,skunkwerks/rocksdb,vmx/rocksdb,caijieming-baidu/rocksdb,caijieming-baidu/rocksdb,virtdb/rocksdb,Andymic/rocksdb,RyanTech/rocksdb,wskplho/rocksdb,bbiao/rocksdb,caijieming-baidu/rocksdb,RyanTech/rocksdb,SunguckLee/RocksDB,alihalabyah/rocksdb,jalexanderqed/rocksdb,siddhartharay007/rocksdb,vmx/rocksdb,bbiao/rocksdb,geraldoandradee/rocksdb,msb-at-yahoo/rocksdb,Vaisman/rocksdb,amyvmiwei/rocksdb,vashstorm/rocksdb,NickCis/rocksdb,ryneli/rocksdb,temicai/rocksdb,facebook/rocksdb,Applied-Duality/rocksdb,tsheasha/rocksdb,wskplho/rocksdb,temicai/rocksdb,Andymic/rocksdb,tsheasha/rocksdb,RyanTech/rocksdb,ryneli/rocksdb,ylong/rocksdb,wskplho/rocksdb,wlqGit/rocksdb,IMCG/RcoksDB,facebook/rocksdb,Applied-Duality/rocksdb,luckywhu/rocksdb,siddhartharay007/rocksdb,biddyweb/rocksdb,vmx/rocksdb,flabby/rocksdb,wenduo/rocksdb,mbarbon/rocksdb,tizzybec/rocksdb,zhangpng/rocksdb,IMCG/RcoksDB,JackLian/rocksdb,fengshao0907/rocksdb,Andymic/rocksdb,luckywhu/rocksdb,dkorolev/rocksdb,wlqGit/rocksdb,wat-ze-hex/rocksdb,mbarbon/rocksdb,hobinyoon/rocksdb,JackLian/rocksdb,tizzybec/rocksdb,ryneli/rocksdb,tschottdorf/rocksdb,JoeWoo/rocksdb,norton/rocksdb,wat-ze-hex/rocksdb,Applied-Duality/rocksdb,IMCG/RcoksDB,tsheasha/rocksdb,bbiao/rocksdb,makelivedotnet/rocksdb,skunkwerks/rocksdb,fengshao0907/rocksdb,RyanTech/rocksdb,norton/rocksdb,tschottdorf/rocksdb,lgscofield/rocksdb,virtdb/rocksdb,wskplho/rocksdb,JackLian/rocksdb,wskplho/rocksdb,luckywhu/rocksdb,Andymic/rocksdb,hobinyoon/rocksdb,caijieming-baidu/rocksdb,sorphi/rocksdb,msb-at-yahoo/rocksdb,hobinyoon/rocksdb,wskplho/rocksdb,IMCG/RcoksDB,geraldoandradee/rocksdb,biddyweb/rocksdb,facebook/rocksdb,hobinyoon/rocksdb,jalexanderqed/rocksdb,Vaisman/rocksdb,NickCis/rocksdb,wat-ze-hex/rocksdb,Andymic/rocksdb,siddhartharay007/rocksdb,vashstorm/rocksdb,JoeWoo/rocksdb,ryneli/rocksdb,dkorolev/rocksdb,tsheasha/rocksdb,siddhartharay007/rocksdb,msb-at-yahoo/rocksdb,JoeWoo/rocksdb,rDSN-Projects/rocksdb.replicated,flabby/rocksdb,ylong/rocksdb,alihalabyah/rocksdb,zhangpng/rocksdb,NickCis/rocksdb,tsheasha/rocksdb,siddhartharay007/rocksdb,anagav/rocksdb,OverlordQ/rocksdb,caijieming-baidu/rocksdb,fengshao0907/rocksdb,JoeWoo/rocksdb,JohnPJenkins/rocksdb,fengshao0907/rocksdb,dkorolev/rocksdb,wenduo/rocksdb,geraldoandradee/rocksdb,kaschaeffer/rocksdb,Vaisman/rocksdb,lgscofield/rocksdb,caijieming-baidu/rocksdb,wenduo/rocksdb,kaschaeffer/rocksdb,rDSN-Projects/rocksdb.replicated,amyvmiwei/rocksdb,mbarbon/rocksdb,bbiao/rocksdb,Applied-Duality/rocksdb,JackLian/rocksdb,wenduo/rocksdb,virtdb/rocksdb,tsheasha/rocksdb,jalexanderqed/rocksdb,tizzybec/rocksdb,tschottdorf/rocksdb,alihalabyah/rocksdb,flabby/rocksdb,OverlordQ/rocksdb,JohnPJenkins/rocksdb,zhangpng/rocksdb,facebook/rocksdb,lgscofield/rocksdb,anagav/rocksdb,wlqGit/rocksdb,zhangpng/rocksdb,wat-ze-hex/rocksdb,biddyweb/rocksdb,rDSN-Projects/rocksdb.replicated,skunkwerks/rocksdb,tschottdorf/rocksdb,kaschaeffer/rocksdb,JackLian/rocksdb,virtdb/rocksdb,facebook/rocksdb,siddhartharay007/rocksdb,OverlordQ/rocksdb,vashstorm/rocksdb,NickCis/rocksdb,SunguckLee/RocksDB,msb-at-yahoo/rocksdb,tizzybec/rocksdb,rDSN-Projects/rocksdb.replicated,amyvmiwei/rocksdb,jalexanderqed/rocksdb,sorphi/rocksdb,bbiao/rocksdb,RyanTech/rocksdb