Welcome to
The Open Source Way. This is our podcast series, SAP's podcast series, about the difference that open source can be. And in each episode, we'll talk with experts about open source and why they do it the open-source way. I'm your host, Karsten Hohage, and in this episode, I'm going to talk to Johannes Bechberger about profilers, SapMachine, or SapMachine one usually says, and about the things that you do. Hi, Johannes.
Hi!
All right.
Great to have you here, Johannes. Johannes is an open-source developer in the SapMachine team. He has been working for more than a year on profilers and their underlying APIs. He started blogging and speaking at conferences in autumn last year, I think it was . Before working at SAP he did his masters in c ompiler engineering in Karlsruhe, and tried to do a PhD for two and a half years. Why didn't that work out anyway?
Because in
the end I found that engineering was my passion, and that when you're in computer science trying to do a PhD it's more about writing papers all the time. And what I wanted, eventually, to do is make the lives of developers actually better, and wanting to contribute to projects, and to make a difference. And I fear that in many parts of the science world you're just writing paper, and that's fine. But for me it's cool that now I see people using my software, and that's far, far, far cooler.
And in the end, I got noticed by other people: 'Hey, SAP has a nice offering. Don't you want to apply?', and I applied, and now I'm here.
I can
totally relate to not wanting to stay in science all your life. I was also at that point, at a certain point in time, but that's a different story. Another different story, as you mastered in c ompiler engineering, that I wanted to point out
. If you go back in our list of podcast episodes we have this very cool talk with Jack Schueler, who is like a veteran of the trade who developed C and C++ compilers back in the, I think back to the 70s even; and in the end was one of the main guys who developed the C++ compiler with which all the great and well known Ego-Shooters, the first-person shooters of the early '90s, were compiled. But anyway, check it out in the list of our podcast episodes. Let's get to you, Johannes.
You work on, or at least you contribute to, quite a few open-source projects, for all I know. One of them is SapMachine, and they are the ones who actually pay your salary, right?
Yes,
that's right. So, I'm working at the SapMachine team at SAP. So, we're essentially working on the OpenJDK, which is the main project that develops Java. And we're the third biggest contributor with our team to the OpenJDK, and we have the maintainer of the JDK 17 on our team. So, if you're using Java 17, even outside of the OpenJDK and even outside of SAP, you're probably using the work of our team, which is quite cool.
And yes, I originally started to work on the SapMachine but then I moved into other open-source profiler fields. And it started like two weeks after I was employed , I started to, as one of my first projects, work on async-profiler. Helping my colleague to fix a bug on PowerPC for async-profiler. And async-profiler is one of the common tools in the area.
And by the
way, if you haven't listened to that, we also have a SapMachine episode that dates back to December 2021. The Jack Schuler one is October 2021, that I mentioned before. And well, do you want to still give a very quick explanation what SapMachine is?
So,
SapMachine is like a distribution of the OpenJDK. Different vendors have different distributions; for example, other companies too but, we work on it, we help to make the OpenJDK better, and help our customers to fix problems with their OpenJDK.
Just
thought we'd mention it because, when we did the JDK episode, we found out that even some SAP colleagues didn't know that there is something like SapMachine around . Now, SapMachine is not entirely why we're here today. We, as I said, had an episode about it. Johannes, you talk, and you write a lot about what you do. That makes me ask you, what does that make you? A blogger, an evangelist, an influencer, a content creator, or what do you call yourself?
I would
first and foremost say that I am like a nerd. I'm a profiler, and tools, and compile nerd. I wanted to be a compiler engineer since school, and wanted to work in this field, and later wanted to do fields and tooling and everything. But yeah, I'm essentially a nerd who wants to spread the word on his creations because it's good when you do some great work but people should know about it.
And so, I feel myself more than like a talkative nerd, a little bit extrovert, but I'm surely not a content creator. But I want to make sure that people know that I'm paid to fix bugs in the OpenJDK and to build tools, not necessarily front and center to do this public work. It's just a side thing that I do because it helps me, and I think we'll get into it in the following minutes, to do my work better.
Yeah, I
didn't really mean that all that seriously. When we speak content creators, or something, we often think of people who show smiling pictures in front of Niagara Falls from the last coding event, or something. No, not from the coding event, just posted. .. Anyway, so did you already say where we find the content that you create, even though you're not a content creator?
So, no,
I didn't. But I can do it right now. So, you'll find my content on Twitter which I use to promote the different things that I do, you find me on InfoQ where I did a recent article, you find me on several conferences near you, hopefully . I'm still in the beginning, so I'm still applying to conferences, and hope I can speak on some. I did speak in London at a QCon in March, and you can find it on my blog. I think the link should be in the description later.
Okay. And
by the way, in a minute or two we'll come, in a little more detail, to what actually Johannes is posting and blogging about. But before we come to that let's examine the channels a little bit more. Does it differ what you post where? Do you post the same things to Twitter as you post to the SAP Community? Or how does that work?
So
essentially, I don't have too much time . Yes, it requires time to address all what I'm doing, so I want to maximize the exposure. So, what I usually do is I post it on my personal blog and on the SAP Community, there you can find the blog post directly after publishing. Then a few days later you find it on Foojay, which is a kind of community, kind of company-run publication, where people can just submit their articles when they're published. And then I tweet about both.
So, people usually follow me on Twitter to see what I'm up on the blog posts. And then for special articles I started writing for InfoQ . I had there one article out which is essentially longer form and original content because it's more these introduction articles and these longer versions that are interesting for a broader audience . Because my blog is more like for the nerds, and InfoQ is for the general software architect.
Okay. And
do you have some things in that like automatized, or something? Like you can say I post this here and then automatically the link is posted to Twitter, and so on?
Sadly not,
because essentially for Twitter I have to write a tagline for the right tweet. And also, all the things I do in Twitter are also mirrored on Mastodon where I also then post a tweet, or "toot" I think it's called, on this blog post.
Well,
anyway, that's quite a lot of channels. Would you say that makes you a Social Media expert?
Kind
of, I'm doing this like for just half a year so, I'm certainly not the expert. I know people from university that study this and they know much more. And I'm also talking with them, what they see on the different channels, which content works best. And I'm like: 'Okay, I'm just doing it.'. So, I think I'm quite good in my niche market; and my niche market is performance experts, and OpenJDK developers, and nerds interested in this topic.
And in this niche market I have a relatively high interaction ratio of my posts. So, for example, on Twitter it's like one tenth of the people that are following me react on my posts usually, and that's quite good. So, I'm kind of an expert. I got better but, I don't know, there are professionals out there who are far better, and I talk with a few of them at conferences, and they gave me some tips. But I'm still at the beginning of my journey, and I don't know where it leads me.
Maybe I'll start a YouTube-Channel, I don't know. Mostly depends on the amount of time that I have, and also on the priorities of my team because I'm paid for this, and it's my team's decision on what I have time to work on.
And by the
way, we're intentionally mentioning rather relative numbers here. Like you said, one tenth of the people interact to posts because, of course, in very specialized topics we're not talking 20 million followers here, or anything. And then the interesting part is what you post interesting to those that do follow you because they're all a small expert community, right. But another thing, you said you got some tips. Do you have any particular tips?
What creates more interest in posts than just simply, I don't know, posting text?
So of
course, I started with blog posts. I didn't have any images and images are hard to create, it takes some time, it takes a few minutes and often more to add images to my blog posts. But I realized these blog posts work better. And also, I can use these images in presentations and on Twitter. So, I want to reduce the overall amount of time that I need to cover all these channels
. And I think blog posts and tweets that are more general in their audience, I had one that went quite well that was 'Writing a Java profiler in 200 lines of pure Java', which was clickbaity, that worked well. But because I write about the things that I'm currently working on, because I'm not creating content that is outside of my current work area, it's quite hard to find too many of these clickbaity things.
So, I would really recommend to stick to your niche, to know your audience, talk with them also like on Twitter, and then really stick to your topic. And please don't be disappointed if in the beginning nobody listens to you because there are many people out there trying to get your attention. And if you have any questions on these topics I think it's good to ask your friends. Maybe there are some influencers around.
You don't know, maybe there are some people that are working in this field, also in the field of marketing, and also ask your local Open Source Program Office maybe they can help you.
I have a
tip for you. If the architecture diagrams that you probably, or things like that, post as pictures take some time to create just use more selfies like the regular influencers.
I think
people don't want to see me, they want to see my content. So, I think that's also a really important thing. You're building kind of a brand of yourself but essentially the people are there for your content. If I would start posting posts on different topics, like I did, I posted a screenshot from a conference talk and people didn't react to it at all - like two likes.
And I was like, okay, the people are really there for the specific niche performance content, and that's the way I grow my audience.
Right, now
that we've said niche for like the fifth time. And we've also mentioned the term "profiler" every once in a while, and I'm pretty sure we're not talking about the guy who tries to understand the psycho killer in the murder case. What are we talking about when we're talking profilers?
I think
that's not a worse understanding of like the Sherlock Holmes out there that's going with his binoculars onto a crime scene and looking it up. But because, essentially , that's what profilers do. Profilers are tools that help developers understand the performance bottlenecks of the application. For example, when you have an outage or when you have performance problems your customers say, 'Oh, there might be something that's a bit slow', you can look into
it. Or also when you're seeing like, 'Hey, we want to save some money, we want to get our application to use less resources.', then you can go out there and look into your application, and that's the task of profiles. And it's essentially a tool for developers to make their applications better.
Okay. And
these run as what? Services, libraries?
It
depends. So, usually people just attach a profiler to their running application and it records. Or there are companies out there that offer it as a service so you can just embed it and it sends data to their service. But I'm working more on the level below, like the tools that the profiler developers use to develop profilers. So, all down on the earth.
Okay. That
is what, like profiler executables, or more like patterns that the profilers probably need to identify what they're supposed to identify.
So, I'm
currently working on this to create a new API for the OpenJDK that helps profiler developers get the key information they need out of the running Java Virtual Machine. And it's one of the largest projects I've ever did. I started on this journey getting it into the OpenJDK in January last year, shortly after I started at SAP, and it's a crazy ride, if I may say so, with ups and downs.
And by the
way, that JDK profiler, that you just mentioned, is that itself also driven as an open-source project or is that your internal project?
So, at
SapMachine we are helping develop open-source profilers, and there are multiple out there. So, what I'm working on is visualizations to visualize data. And also currently, as I said on the APIs that profiler developers use, on methods in the OpenJDK that the profiler developers use to get out their information.
I think
I'm getting a pretty good picture. And if I'm getting a pretty good picture everyone out there probably has a better picture. So let's return to the advocating business. How did that even come about that you got into that? How did you become one of those extrovert developers, which some may consider an oxymoron almost? I mean, like most colleagues are, how do you experience that, are not all too keen on going public with their stuff all the time, right?
So, I
experienced this with my colleagues when I'm telling, and also friends, when I'm telling them I'm going to a conference. And most of them are like, 'Why?' . And so, it was for me the same. But I talked with a friend, who pushed me into this, a few weeks back and we talked about how it all started. And I asked a local Java User Group, 'Hey, I do something on profiling, can I just do a talk on the profiling stuff?'. And they were like, 'Yeah', and 'Come
on'. And then I was persuaded by my friend to write a blog post on all the material that I found online that I used to prepare my talk. And this blog post went quite well, for the time it gathered some attention, and people asked me, 'Hey, that's cool. Go for it .', and asked me that I publish it on Foojay. And so, I grew my audience a little bit. And then in January this year the QCon London people asked me, 'Hey, can you come to London in March and give a talk on your topic?'.
And I'm like, cool. I quite liked it, being there in London on a stage, talking to 100, 150 people, and some of them liked it too, so it was quite encouraging to get good feedback. And now I'm hoping that it's not the last conference that I'm on, and I'm also going to Java User Groups out there. So if you're in a Java User Group, I can come to you too, and talk about this topic.
Okay,
here's the advertisement part. Do invite Johannes as a speaker! And you said you quite like it. What does it gain you, or why would you say that everyone should think more about talking about their stuff?
A good
comparison is when a tree falls in the forest and nobody notices, is the tree really falling? You can develop the best profiling APIs out there, you can develop the best profiling visualizations. If I don't go to conferences, for example, and tell people about, 'Hey, here's a cool new thing.', then people won't notice. And for example, I created a wrapper around the profiler because this profiler has binary and it isn't that platform-independent because it's hard to use, whatever.
And I wanted other people to use it because that's also great for our team because then we can say, 'Hey, we were one of the building blocks of the profiling infrastructure.'. And I use my Twitter following to say, 'Here is the great new tool, please use it.' And it helped. So, essentially it gives awareness to my products, and also it builds my personal brand.
So, I gain personally from it that I can go to conferences, see new cities, talk with many cool people, and sometimes even friendships come out of this. For example, in a few weeks I'm going to Munich to visit a friend there, who I met at a conference in London. And so, yeah, it works quite well for me, and might work for you also.
All right.
And just to be clear on that, you do things in your profiler topic that are closely related to OpenJDK, and thus also SapMachine. But you actually do this on your own accord, right? This is not necessarily part of your job profile here, or is it?
The job
profile when you work on like open-source stuff is quite vague usually. So, in the beginning it wasn't part of my job profile, I didn't think about this. But then I asked around in my team, I asked my manager, and he was okay with me going out there. And now, for example, here at the open-source podcast for the second time as our team and can promote the cool SapMachine project. So, I think it works out quite
well. So, it's not directly in my job description but it's also not a hobby thing that I'm doing. I'm paid to be there, I'm going there during my working hours on conferences, and I'm working mostly during my working hours on this open-source project. So they are not hobby projects.
Let's
leave the hobby term out of that. I think that's a very difficult one because many people do something aside their main job that is still way more than you usually call a hobby, I would say. Anyway, what I think I understood is that when you started at SAP, you didn't know you would be doing this kind of public stuff, but you did know that you would be in the open-source field, right?
Yes, this
was one of the cool things. When I applied for the job, they were like, here's this open-source job and you can work on the OpenJDK - And I was like, cool. And then I asked a friend how the team is and he is like "These are cool open-source people - go to them !" And I'm like, okay, cool. So SAP having these jobs related to open source definitely was a reason for me to come to SAP, and why I like working here.
All right.
So, Johannes is actually an argument for attracting young talent by doing open source, everyone out there. You wouldn't be with SAP if we were not doing open source. And then with your public things that you do, is that, would you say, that also promotes more the fact that SAP does open source and promotes open source? Or does it more promote your own personal brand, or is that not clearly separable? Or how is that?
I think
it's clearly not that separable because, for example, it promotes myself, of course, because I'm the one standing in front of it. Also, when I was at FOSDEM in February this year I started my slides off with like, 'Hey, SAP does open source .'. Because SAP is a large open-source contributor, but people don't know this. So many people think, okay, SAP just develops this large application that many, many businesses
use. But they don't know that they are active, for example, that they have their own open-source UI framework, called SAPUI5, or that they worked on the open source Corona-Warn-App that was quite popular for a time in Germany. So, I think people get with my talks, get awareness and see, 'Oh, SAP is doing this - cool.' And also, I'm getting in touch with people of different companies. It later helps when we have a problem, and I can just ask around in the field of experts.
They're always like 'Oh, this small technical problem, can you help me with this? I know you're an expert .', and because we're like in the open-source field it's far easier for them to just give me the answer without all this asking around the boss. And so, because we're contributing to a common good.
All right.
That would actually totally qualify for the, I'm translating directly from German, the saying would be: "Swatting several flies with one strike.", right? You're promoting your personal brand. You're promoting that SAP actually does open source, and thus promoting the general SAP brand. You're promoting the particular projects. Great. Now, as we have, I think, all that down.
That if you do interesting stuff then also go out there and talk about it because otherwise, you're the tree in the wood that falls without anyone hearing it. Or if, as we say among us content creators: 'Pictures, or it didn't happen!' Anyway, famous before-last question: Where do we find all that? You mentioned some of those things, but would you want to summarize again?
Yeah,
you'll find me on my personal blog. You'll find me on smaller conferences like the Karlsruher Entwicklertage, and hopefully more conferences near you. Follow me on Twitter for more updates. And as I said, if you want me to come to you, maybe let's chat. And around the time this will be broadcasting I'm hopefully in Milan being at the Java User Group there and talking about the topic of profiling, as I like to do.
Yeah, and
here is another one we didn't even mention: It makes you get around and see places, right?
Of course,
seeing London for the first time in 15 years is quite cool. And being in Westminster, in the city center, for a few days is quite interesting. But of course, it's also work, it takes some effort. It's also quite stressful when you're standing in front of so many people, but it's a cool experience.
Okay,
let's not focus on the stress that much. The three key takeaways, totally stress free. What would you want our listeners to remember from this episode? And by the way, the links to some of the content we'll put under the podcast, of course.
So, I
want the listeners to see that open source matters. It really helps you, and your brand, and also your team . And just start writing a blog, tweeting about it and it doesn't take that much time, it takes a couple of hours. When you do it regularly, you'll attract an audience eventually, after a few weeks, after a few months, but you'll get there. It's a fun journey and it brings you further. And then my last point is: spread the word, but stay focused on your niche!
So, don't stray too much from your core topic, and just have fun, and don't stress too much.
Okay.
Thank you very much, Johannes, for being our guest today. It was great to have you here.
Thank you
for having me.
All right.
And then thanks everyone out there for listening to The Open Source Way. If you enjoyed this episode, please share it and don't miss our next episode, published every last Wednesday of the month. You'll find us on OpenSAP and in most of the places where you find your other podcasts like Apple Podcasts, Spotify, and the likes. Thanks again and bye bye.