Voice of the DBA

Author: way0utwest

  • The Complexity of Metrics

    Monitoring your SQL Server instances is important to ensure you can meet your SLAs. Availability, performance, reliability, quality, whatever you care about, it’s important that whoever is responsible is looking at how the database is performing. At Redgate, we have multiple teams working on SQL Monitor to enhance and grow it to meet your needs.

    A short while ago there was an internal conversation recently about page life expectancy. We’ve had some customers ask about this and setting alerts to watch this value. Our developers and sales engineers asked for a few thoughts from Grant and others on how to respond. There are a variety of opinions, some saying monitor it, some saying don’t bother.

    I think both pieces of advice have merit, which is to say that this isn’t a metric that you can look at in isolation. There is no value of PLE that is good or bad, or that says x is wrong or y is right. There is both a subtlety and a complexity to understanding what PLE is telling you about your system. If PLE is growing, you have to look deeper. If it’s falling, same thing. If it suddenly drops, there are multiple possible causes, and you need to examine other things. However, in many cases, this isn’t an actionable metric, but one that provides context about what might be happening in the database when combined with other values you monitor.

    This certainly isn’t a metric that you want to set an alert on because it can rise or fall and many times the change isn’t indicative of an acute problem.

    This is just one metric of many that are available in SQL Server, and knowing which ones to monitor is something good administrators learn. They know that very few values they instrument have a good or bad value, and often the rate of change needs to be combined with the actual reading to determine if there is a problem. We also often want to know if a high (or low) reading appears for an extended period of time. Having 100% CPU being used for 3 minutes likely isn’t an issue. If it lasts for 3 hours, I might feel differently.

    Metrics have more complexity than just having a range in which we ignore them and a limit at which we alert people. They are intended to be combined with each other, with observations by clients, and with the experience of looking at past observations over time. Our systems often develop patterns, and we don’t get too concerned about any values when the pattern repeats. It’s when something new happens and someone complains that we dig in to determine if there is a problem or the start of a new pattern.

    We definitely need monitoring of our database metrics, but we also need to understand why values move and the implications of them doing so. That’s something which isn’t as simple as setting alert for each one based on some value we think should never be exceeded.

    Steve Jones

    Listen to the podcast at Libsyn, Stitcher, Spotify, or iTunes.

  • Daily Coping 30 Jan 2023

    Today’s coping tip is to plan something fun and invite others to join you.

    The fun thing is actually skiing today. My wife and I wanted to get some time away with our kids, so we invited them to come to Keystone for Sat/Sun/Mon for a getaway. They’re joining us, though some are leaving tonight to return home for work tomorrow, while we’re staying another day.

    I started to add a daily coping tip to the SQL Server Central newsletter and to the Community Circle, which is helping me deal with the issues in the world. I’m adding my responses for each day here. All my coping tips are under this tag.

  • Speakers Are Normal People

    The #SQLFamily is amazing, at least I think it is. Like many families, it’s welcoming, supportive, and comforting. It’s also maddening, frustrating, and exacerbating at times. Like most families, or at least the ones I know, it’s not perfect, but it’s what we have and at the end of the day, most of us get along with each other.

    It’s also an open group of people. In general, we welcome people with open arms and smiles. Those of us that are more visible or prominent are willing to listen to, help, and support anyone. I was overjoyed during the recent PASS Data Community Summit, where I had the chance to see so many people that I haven’t seen in person in 2-3 years. I met many other interesting people for the first time and enjoyed the experience.

    Not everyone feels the same way. I loved seeing Kimberly Tripp and Paul Randal for the first time in years and was honored to share the stage with them for the Community Keynote. I enjoyed the time we spent together, but afterwards Paul wrote about some people not feeling included or welcome.

    I understand that feeling. In many ways, much of adult life can mimic teenage years in high school with cliques and pettiness. I won’t pretend that doesn’t happen in the #SQLFamily, but I find it quite minimized, especially compared with many other communities of which I’ve been a part in the past. I haven’t seen the higher profile speakers and leaders in the SQL Community dismiss someone for asking a question or expressing an opinion. I have, however, seen that in other communities.

    It can be intimidating to walk up to someone that you don’t know who you might feel is famous or well known. It can be intimidating to just walk up to a group of people who are talking when they appear to know each other. I have that feeling at times even today, so I appreciate feeling like an outsider. In the Summit keynote, I talked about the thrill in meeting Kalen Delaney in 1999 and shaking her hand. I was nervous and intimidated to ask her a question after her presentation. At the time I hadn’t delivered a talk in front of anyone outside of school environments and was a fairly introverted geek. It was hard to step up and make that effort, but I’m glad I did.

    As Paul writes, anyone is welcome in the #SQLFamily. Anyone can join. You don’t have to come shake a hand or say hi, but I’m happy when you do. Will we be best friends right away? Probably not. Will we go out to dinner that night? Maybe. I’ve certainly met attendees at events and then had dinner with them. I know plenty of other speakers who have as well.

    Many of the people who speak, organize, and write/blog/tweet/etc. in our industry are friends. We do value time with each other, and that can feel like a club, but it’s not. We enjoy seeing each other and want to catch up, like any group of friends. However, we are also welcoming of newcomers, so feel free to introduce yourself.

    Ultimately those of us who engage in these highly visible, extroverted acts are often just like the rest of you. We’re a mix of people that are mostly introverted, with a few extroverts thrown in. Some speakers are very smart and talented, some are more like me: we know enough to get the things done that we’re asked to do.  Some of us love to go out and sing karaoke until all hours of the night and others prefer a small dinner or a little tabletop gaming in a quiet environment.

    My encouragement to get people to meet others, network, set up events or meetups, and more isn’t to try and convince any of you to join the cool kids club. It’s not to get you to change who you are.

    It’s to help you find your tribe. To find your kind of people.

    I’d love to greet all of you with a hug at events, call you by name, and go out to dinner with you. I can’t because there isn’t enough time in the day. And quite frankly, I really, really value my alone time. What I want more than anything is for you to be successful, find a great job or career you relish, and for you to enjoy spending time with those you enjoy. Whoever and wherever that is. That takes some effort, but it’s worth the energy involved.

    Steve Jones

    Listen to the podcast at Libsyn, Stitcher, Spotify, or iTunes.

  • Daily Coping 27 Jan 2023

    Today’s coping tip is to try something new to get out of your comfort zone.

    I did two things here. First, I’ve been participating in a Jan American Cancer Society Challenge and fundraiser. I’m doing this because cancer sucks, and I wanted to help. I rowed in college, but I don’t want to just focus on rowing, so I’ve been trying to fit this into my normal routine.

    However, I decided to go longer and make this my exercise for a few days. Part of that is being busy and bad weather, part to change things up. I pushed harder and instead of a 10-12min row, I went 22 and 5k.

    Second, I asked my son to cook a recipe. He showed me something he found interesting, which usually results in me asking for the URL and I shop and cook. This time I asked him to make it, which is slightly uncomfortable for me. However, I’ve been extra busy, so I got out of my comfort zone.

    I started to add a daily coping tip to the SQL Server Central newsletter and to the Community Circle, which is helping me deal with the issues in the world. I’m adding my responses for each day here. All my coping tips are under this tag.