November 2021
Intermediate to advanced
410 pages
12h 1m
Chinese
Content preview from MongoDB权威指南（第3版）
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303
第 18章
了解应用程序的动态
应用程序启动并运行后，要如何知道它在做什么呢？本章介绍如何了解
MongoDB
正在运
行哪些类型的查询，有多少数据正在被写入，以及其他有关它实际在做什么的细节。我们
将学到：
•
找出并终止慢操作；
•
获取并解析有关集合和数据库的统计数据；
•
使用命令行工具来获得
MongoDB
正在做什么的信息。
18.1
查看当前操作
发现慢操作的一个简单方法是查看正在运行的操作。速度慢的操作耗时更长，更有可能被
发现。虽然并不能完全保证，但这是一个不错的开始，可以看到是什么导致应用程序变慢。
要查看正在运行的操作，可以使用
db.currentOp()
函数：
> db.currentOp()
{
"inprog": [{
"type" : "op",
"host" : "eoinbrazil-laptop-osx:27017",
"desc" : "conn3",
"connectionId" : 3,
"client" : "127.0.0.1:57181",
"appName" : "MongoDB Shell",
"clientMetadata" : {
"application" : {
"name" : "MongoDB Shell"
},
"driver" : {
304
｜
第
18
章
"name" : "MongoDB Internal Client",
"version" : "4.2.0"
},
"os" : {
"type" ...
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