Paging i / o . these are i / o operations initiated by the virtual memory system in order to satisfy the needs of the demand paging system 這類是為了滿足“請(qǐng)求頁(yè)面調(diào)度系統(tǒng)”的需求而由虛擬內(nèi)存系統(tǒng)發(fā)起的i / o操作。
Shared virtual memory system builds one svm layer over physically distributed memory to form one logically uniform shared virtual space 虛擬共享存儲(chǔ)系統(tǒng)( svm )用軟件的方式在物理分布的存儲(chǔ)器上實(shí)現(xiàn)了一個(gè)邏輯上統(tǒng)一的虛擬共享存儲(chǔ)空間。
For this reason , there are specific rules used to ensure correct cooperation between file systems ( and file system filter drivers ) and the virtual memory system 正是由于這個(gè)原因,有詳細(xì)明確的規(guī)則用于保證文件系統(tǒng)(過(guò)濾)驅(qū)動(dòng)程序與虛擬內(nèi)存系統(tǒng)之間正確的協(xié)作。
But it has deficiencies - collection pauses can be long , and the entire heap is visited in the sweep phase , which can have very negative performance consequences on virtual memory systems where the heap may be paged 但是它也有不足收集暫??赡軙?huì)很長(zhǎng),在清除階段整個(gè)堆都是可訪問(wèn)的,這對(duì)于可能有頁(yè)面交換的堆的虛擬內(nèi)存系統(tǒng)有非常負(fù)面的性能影響。