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Free, simple code to find out what SQL statements are running slow in SQL Server right now

Note: This blog post is from 2015. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
Often when people are trying to troubleshoot seeming problems in ColdFusion (or whatever app server you may use), they may wonder if (or have tools which suggest that) their CF requests are being held up waiting for a query to run in the database, which seems hung up.

Wouldn't it be nice to know, at any moment (such as when things are going badly), just what queries (or stored procedures or commands) were running in the database at that point in time?

Well here's good news: if you're running SQL Server, the following SQL query will show you just that: the currently running SQL statement(s) and some additional details about each query including their duration, their database name, the program executing the SQL, the session id, and much more.

For more (including why things like Activity Monitor's "recent expensive queries", sp_who2, and others aren't the answer, as well as what to do if you may be unable to run this code), please read on. (I also mention the classic sp_whoisactive as another solution, and have updated this post since its 2015 writing to mention the newer "active expensive queries" in Activity Monitor, which you may find in later versions of SQL Server, both of which you can consider in addition to the below.)

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Understanding SQL Server Statistics: A great, free, relatively brief ebook

Note: This blog post is from 2015. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
If you want to understand the important concept of SQL Server statistics (a mechanism within SQL Server which tracks metadata about your data, and which can significantly affect query performance if not managed well), I think you can do no better than than to spend an hour or so reading the free 40-page e-book, SQL Server Statistics, written by Holger Schmeling and offered by Red-gate. book cover

The book is a quick read, and really well done, including a discussion of what statistics are, why they're important, how to diagnose trouble with them, and how to use the SSMS interface and/or SQL statements/commands to better understand them.

There are plenty of screenshots and it's written in a tutorial manner. And while it's from 2010 and covers only up to SQL Server 2008, most of the concepts apply just as well to SS 2012 and beyond, and of course many organizations are still running on SS 2008 or even earlier!

Most important, Schmeling explains why it's important that you take responsibility to both create and maintain statistics (rather than leave it as something that "the database" should handle. And if you are leaving it as something "the db should handle", you can use this to make sure that person is doing their job with respect to statistics.)

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Solving slow CF startup: my elaborating on an Adobe blog entry on a possible solution

Note: This blog post is from 2015. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
The fine folks at the Adobe CF blog posted a blog entry today, on "Sometimes ColdFusion services refuse to start normally post server restart" (by Rahul Upadhyay), which offers some helpful information on one possible solution to the stated problem of slow CF startup.

That said, there are some concerns I have, with respect to how I fear some may read and take action based on it (especially the notion of deleting the cfclasses files, as a possible solution to the problem).

I'm not contradicting Rahul here, just elaborating on some points, as someone who (like some on the CF team) helps people with CF server troubleshooting every day.

I started to write these thoughts as a comment there, and (as often happens) it grew long so I thought it better to be a blog entry rather than a long comment, and point people here. Once I did that I decided to go further still, hoping to really help those interested to consider the issue more carefully. (It also gives me a chance to highlight again the Adobe CF team blog, something I recommend EVERYONE reading this should follow!)

One quick point (and update) for the TL;DR crowd: My recommendation is that you move the cfclasses folder out of that location, as a temporary test, to see if it makes CF startup happen faster. If it does, I explain why and what the implications are in the choices of renaming, deleting, moving, or disabling the related "save class files" feature. Also, I add an update in E.1 below (since posting this) which you may really want to read: consider turning off your anti-virus software's real-time protection against the cfclasses folder to see if that alone helps with startup.

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CF911: 'Help! I've updated the JVM which ColdFusion uses, and now it won't start!'

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
[Originally posted in Dec 2014, updated as recently as Apr 2021]

Has this happened to you? You wanted to update the JVM which CF uses to use a new version...

  • so you found some resource on the web showing how to update, and it seemed simple enough
  • and then you tried restarting CF and wham, it won't start, or the admin won't open, or code starts failing
  • and maybe it's that things didn't fail immediately, but within hours or days folks report things breaking since you made the change
  • and now you're stuck wondering, "what happened? and how am I supposed to fix this?"

It's a tough position to be in, and tragic of course if CF won't start. But no, you do NOT need to reinstall CF!

Often it's just one thing you did by mistake, though there are indeed several possible reasons why your attempt to update CF's JVM can fail or lead to unexpected problems. And as you google about, you may find all kinds of helpful but often misinformed or spartan suggestions that may or may not help much.

So I offer here over a dozen of things you can and should consider/look at, some of which you may quickly recover from or be able to undo (depends on what you did). And all this applies to Lucee, Railo, and BlueDragon as well, though folder locations will differ.

If you're facing this bind right now, you can skip over the following to the the section, "Seeing better error info, when the CF service won't start", and then the section after that "So what went wrong?", where I present each likely problem and solution.

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My reply to: 'The price for CF troubleshooting consultants is a joke. They're taking us for a ride'

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
Ok, so that's clearly not my sentiment but rather that of a certain "Simon" (no other identifying info offered) in a blog comment in one of the recent CF team blog entries.

After complaining about how poorly he felt CF had responded to his seeking help, he threw in additionally that "the existing private consultants prices are a total joke - they are taking us for a ride!".

Well, I just couldn't let go his comment go unremarked.

I started to write my reply there, but it grew long (as is my wont). So rather than post there (where most comments are brief), I decided to post it here instead and point to it there. Perhaps some of my readers here may appreciate it as well, as I also talk about some thoughts on CF troubleshooting in general.

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My New Youtube Video on the Why and How of Using FR Stack Traces for ColdFusion Troubleshooting

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
As many of my readers know, I'm a big fan of the FusionReactor server monitor for ColdFusion (and Railo, BlueDragon, Tomcat, and indeed any Java server). I help people use it every day (just like I also help people leverage other CF monitors like the CF Enterprise Server Monitor and SeeFusion).

One of the most important features is the stack tracing feature, used to understand what's holding up a long-running request.

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CF911: High CPU in ColdFusion? Some common but perhaps unexpected causes

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
I often help people who are reporting that CF is "running hot on the CPU", maybe reaching 80 or even 100% of the CPU, whether in spikes or for extended periods. What might you propose people look at, when you've heard that? I've heard all kinds of things over the years, often focused on coding, or perhaps jvm tuning.

But as is often the case in a lot of the CF server troubleshooting consulting I do, I find the causes to be far less often what most people seem to suspect. So what would I look for when someone reported high CPU in ColdFusion (or Lucee or Railo )? Read on.

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proXPN users: a simpler soluton for "Connecting to proXPN has failed"

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
If you're a user of proXPN (a free/low-cost VPN service), and you get the error, "Connecting to proXPN has failed", here is a simple solution that you may not find offered elsewhere: just try restarting proXPN. For more information, read on.

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CF911: Solving problem in ColdFusion Admin getting "error accessing this page" on certain actions

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
Here's a real CF911 challenge (and solution): You may find that when using the CF Admin, especially in CF10 but it can happen in CF 9 or 8 depending on security hotfixes applied, when performing certain Admin operations (like making a change, or verifying datasources, or checking for server updates) you get an error:

"There was an error accessing this page. Check logs for more details."

And your operation fails. You're then prompted to "Click here to login", but even if you back up or client another link, you'll be prompted with the CF Admin login.

What gives? Why is it happening? And how can you fix things? Is CF broken? No, not in the sense that you need to reinstall or anything. The good news is that there is a quite simple solution. Well, there are several, depending on your goals.

The simple solution: delete the duplicate cfid/cftoken or jsessionid cookies that you will find your browser is sending to CF. But there is much more to this, as well as other solutions, which would be worth most readers taking a few minutes to read on here.

BTW, the same root problem can be the cause of your own application's users finding that they can't stay logged in. More on that in a moment.

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Applying hotfixes to ColdFusion 9 and earlier? A guide to getting it right

Note: This blog post is from 2014. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.
I realize that title may seem anachronistic. Why talk about hotfixes in CF9 and earlier, in 2014, indeed as CF11/Splendor is in beta? But I'll tell you that I still help people daily who are still on those older releases, and often they have problems that may have long since been solved by a hotfix or a cumulative hotfix they never applied--or may be caused by misapplication of such hotfixes.

Of course, in CF10 it's easier now because of the built-in "server updates" feature of the CF Admin. But in earlier releases, it was all on you to both keep up on the updates and to apply them manually. And a lot of people either never bothered, or may have tried and failed, or did it but got it wrong.

What you need to know

So in this blog entry, I some key info that will help you, if you may be in need of applying one or more of those updates to CF9 and earlier. Indeed, I'll point to some past entries I've done where I shared a lot more detail that I find is vital and rarely mentioned when some people try to share just the bare minimum of info (often leaving people hanging).

For instance, I'll help you answer such questions as what hotfixes do you already have applied? How do you find out? And you need to know exactly what version of CF you have, whether 9.0/9.0.1/9.0.2, 8.0/8.0.1, 7.0/7.0.1/7.0.2, and so on. I'll explain how to tell and why that's important, and especially when it comes to finding and applying hotfixes. And if you have applied hotfixes, are you sure you have done it right? It's easy to get things wrong and botch things. I'll help you avoid several very common mistakes.

(That's why it's so great that CF10 finally handles things for us. But this entry, focused on 9 and earlier, is not the place to discuss concerns with the CF10 hotfix mechanism. If you have questions or concerns about that, see the substantial CF10 Hotfix Installation Guide from Adobe, a 50-question FAQ on all things related to that feature.)

I'll also point you to where to find hotfixes and installers for CF9 and earlier (not as easy as it may seem), and still more.

If any of that's of interest, and I hope it is if you're on CF9 or earlier, then read on.

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