Background
It was quite some time ago that I wrote my Five-Minute Page Performance Troubleshooting Guide for SharePoint Online – a little over a year-and-a-half ago, actually. Since that time, SharePoint Online (SPO) has continued to evolve relentlessly. In fact, one slide I’ve gotten into the habit of showing during my SPO talks and presentations is the following:
The slide usually gets the desired response of laughter from attendees, but it’s something I feel I have to say … because like so many things that seem obvious, there’s some real life basis for the inclusion of the slide:
The exchange shown above was the result of someone commenting on a post I had shared about limitations I was running into with the SharePoint App Model. The issue didn’t have a solution or workaround at the time I’d written my post, but Microsoft had addressed it sometime later.
This brief exchange highlights one of the other points I try hard to make while speaking: PAY ATTENTION TO DATES! It’s not safe to assume (if it ever was) that something you read online will stay accurate and/or relevant indefinitely.
In any case, I realize that much of what I share has a “born on date,” for lack of a better label. I’ll continue to share information; just note when something was written.
End of (slight) rant. Back to the real topic of this post.
Modern Pages
Since I had written the previous performance article, Microsoft’s been working hard to complete the transition to Modern SharePoint in SPO. I feel it’s a solid move on their part for a variety of reasons. Modern pages (particularly pages in communication sites) are much more WYSIWYG in nature, and SharePoint Framework (SPFx) web parts on modern pages make a whole lot of sense from a scalability perspective; after all, why assume load on the server (with classic web parts) when you can push the load to the client and use all the extra desktop/laptop power?
As good as they are, though, modern pages don’t obey the standard response header approach to sharing performance metrics. But not to worry: they do things more consistently and reliably (in my opinion).
Performance on a Modern Page
SPRequestDuration (the amount of time the server spent processing the page request) and (SP)IISLatency (the amount of time the page request waited on the server before getting processed) are critical to know when trying to diagnose potential page performance issues. Both of these are reported in milliseconds and give us some insight into what’s happening on the server-side of the performance equation.
Instead of trying to convey these values with response headers (as classic pages do – most of the time), modern pages share the same data within the body of the page itself.
Consider the following page modern page:
If this were a classic publishing page and we wanted to get the (SP)IISLatency and SPRequestDuration, we’d need to use our browser’s <F12> dev tools or something like Fiddler.
For modern pages, things are easier. We turn instead to the page source – not the response headers. Grab the page source (by right-clicking and selecting View page source) …
… and you’ll see something like the following:
Now, I’ll be the first to admit that you’ve got to have some sense of what you’re seeking within the page source – there’s a lot of stuff to parse through. Doing a simple <CTRL><F> search for iislatency or requestduration will land you on the content of interest. We’re interested in the metrics reported within the perf section:
The content of interest will be simple text, but the text is a JSON object that can be crunched to display values that are a bit easier to read:
The other thing you’ll notice is that a lot of additional metrics are reported along with the page processing metrics we’ve been looking at. In a future post, I’ll try to break some of these down for you.
Conclusion
“Modern” is the future of SharePoint Online. If you haven’t yet embraced modern lists and pages, consider dipping your toe in the waters. As we’ve seen in this post, Modern also makes it easier to obtain performance metrics for our pages – something that will make page performance troubleshooting significantly more predictable and consistent.
References and Resources
- Blog Post: Five Minute Page Performance Troubleshooting Guide for SharePoint Online
- Office.com: SharePoint Classic and Modern Experiences
- Office.com: What Is A SharePoint Communication Site?
- Microsoft.com: Overview of the SharePoint Framework
- MDN: Response Header
- Telerik: Fiddler
- JSON Viewer: Code Beautify
