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What is Reslen in MongoDB?
responseLength (reslen): – The length in bytes of the operation’s result document. A large responseLength can affect performance. nscanned: – The number of documents that MongoDB scans in the index in order to carry out the operation.
What is numYields MongoDB?
According to MongoDB doc: numYields is a counter that reports the number of times the operation has yielded to allow other operations to complete. Typically, operations yield when they need access to data that MongoDB has not yet fully read into memory.
Why does profiler use in MongoDB?
The database profiler collects detailed information about Database Commands executed against a running mongod instance. This includes CRUD operations as well as configuration and administration commands. The profiler writes all the data it collects to a system.
What is MongoDB getMore?
Definition. getMore. New in version 3.2. Use in conjunction with commands that return a cursor, e.g. find and aggregate , to return subsequent batches of documents currently pointed to by the cursor.
What is MongoDB collection?
A collection is a grouping of MongoDB documents. Documents within a collection can have different fields. A collection is the equivalent of a table in a relational database system. A collection exists within a single database.
How does MongoDB log all queries in real time?
Especially it can help diagnose issues with larger scale mongo systems and how queries are being routed and where they are coming from since it works by listening to your network interface for all mongo related communications. I wrote a script that will print out the system.profile log in real time as queries come in.
What is the default log verbosity level in MongoDB?
0 is the MongoDB’s default log verbosity level, to include Informational messages. 1 to 5 increases the verbosity level to include Debug messages. To inherit the verbosity level of the component’s parent, you can also specify -1.
Which is the default runtime for MongoDB?
By default slow operations are those slower than 100 milliseconds. You can modify the threshold for “slow” operations with the slowOpThresholdMs runtime option or the setParameter command.
What is the default profiler level for MongoDB?
Level 0 – the profiler is off, does not collect any data. mongod always writes operations longer than the slowOpThresholdMs threshold to its log. This is the default profiler level.