How To Collect Latency Stats?

[theironcook]

Hi,

I'd like to measure the average latency per request from my app servers to my mongo database.  Every minute, I want to log out the average db transaction time from the app servers perspective.  This type of data has helped me trouble shoot issues in the past.

import * as mongoose from "mongoose";

...

this.mongoose.connection['db']['stats']((err, stats) => {

if (err) {

metricsLogger.logKeyValues( { ERROR: err });

return;

}

metricsLogger.logKeyValues({AvgObjectSize: stats.avgObjSize, fsTotalSize: stats.fsTotalSize,

fsUsedSize: stats.fsUsedSize});

});

Here's some sample code I'm playing around with.  The stats object contains data that looks like this: 

  db="xxx" collections="1" views="0" objects="75" avgObjSize="731.3466666666667" dataSize="54851" storageSize="45056" numExtents="0" indexes="1" indexSize="36864" fsUsedSize="6353461248" fsTotalSize="43985149952" ok="1"

I'm hoping that there are latency and request count statistics somewhere stored in the mongoose connection...  Or maybe someone knows if I can intercept all requests and capture my own latency metrics manually somehow?

Thanks,