Ruby's Global VM Lock

Stephanie is joined by very special guest, fellow thoughtboter, Senior Developer, and marathon trainer Mina Slater.

Mina and Stephanie had just been traveling together for two weeks, sponsored by WNB.rb for RubyKaigi in Matsumoto, Japan, and together, they recount their international adventure!

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• RubyKaigi
• WNB.rb
• Understanding the Ruby Global VM Lock by observing it by Ivo Anjo
• gvl-tracing
• Justin Searls' RubyKaigi 2023 live coverage
• Prioritizing Learning episode

Transcript:

STEPHANIE: Hello and welcome to another episode of The Bike Shed, a weekly podcast from your friends at thoughtbot about developing great software. I'm Stephanie Minn and today. I'm joined by a very special guest, fellow thoughtboter Mina Slater. Mina, would you like to introduce yourself to our audience?

MINA: Yeah. Hi, everyone. I am Mina. I am a Senior Developer on Mission Control, which is thoughtbot's DevOps and SRE team.

STEPHANIE: So, Mina, what's new in your world?

MINA: Well, I start marathon training this week. So I hope that this conversation goes well and lasts you for three months because you're probably not going to see or hear from me all summer.

STEPHANIE: Yes. That sounds...it sounds hard, to be honest, marathon training in the summer. When I was doing a bit more running, I always thought I would wake up earlier than I did and, you know, beat the heat, and then I never would, and that really, like, was kind of rough.

MINA: Yeah, actually, I was thinking about my plans for today. I didn't wake up early enough to run in the morning. And so I was calculating, like, okay, by midday, it's going to be too hot. So I'm going to have to wait until, like, 6:00 p.m. [laughs]

STEPHANIE: Yeah, yeah. Or, if you're like me, there's a very real chance that you just skip it altogether.

[laughter]

MINA: Well, I have a deadline, so... [laughs]

STEPHANIE: That's true. When is your marathon race?

MINA: This is actually the first year I'm doing two in a calendar year. So I'm doing Berlin in September. And then, three weeks after that, I'm going to run one in Detroit.

STEPHANIE: Nice. At least you'll be ready. You'll, like, have done it. I don't know; it kind of sounds maybe a bit more efficient that way. [laughs]

MINA: Theoretically. But, you know, ask me in October. I'll let you know how it goes.

STEPHANIE: That's true. You might have to come back on as a guest. [laughs]

MINA: Just to talk about how it went. [laughs]

STEPHANIE: Yeah, exactly.

MINA: So that's what's new with me. What's new in your world, Steph?

STEPHANIE: So, a while back on a previous Bike Shed episode, I talked about joining this client team and, in their daily team syncs, in addition to just sharing what we were up to and what we were working on, we would also answer the question what's something new to us. And that was a space for people to share things that they learned or even just, like, new things that they tried, like food, or activities, or whatnot. And I really enjoyed it as a way to get to know the team, especially when I was new to that client project.

And recently, someone on the team ended up creating a random question generator. So now the question for the daily sync rotates. And I've been having a lot of fun with that. Some of the ones that I like are, what made you laugh recently? What's currently playing on your Spotify or YouTube? No cheating.

MINA: [laughs]

STEPHANIE: And then, yesterday, we had what's for dinner? As the question. And I really liked that one because it actually prompted me to [chuckles] think about what I was going to do for dinner as opposed to waiting till 5:00 p.m. and then stressing because I'm already hungry but don't have a plan [chuckles] for how I'm going to feed myself yet. So it ended up being nice because I, you know, kind of was inspired by what other people mentioned about their dinner plans and got my stuff together.

MINA: That's shocking to me because we had just come off of two weeks of traveling together. And the one thing I learned about you is that you plan two meals ahead, but maybe that is travel stuff.

STEPHANIE: I think that is extremely correct. Because when you're traveling, you're really excited about all the different things that you want to eat wherever you are. And so, yeah, we were definitely...at least I was planning for us, like, two or three meals [laughs] in advance.

MINA: [laughs]

STEPHANIE: But, when I'm at home, it is much harder to, I don't know, like, be motivated. And it just becomes, like, a daily chore. [laughs] So it's not as exciting.

MINA: I think I'm the same way. I just had a whole bunch of family in town. And I was definitely planning dinner before we had breakfast because I'm like, oh, now I have to be responsible for all of these people.

STEPHANIE: Yeah. I just mentioned the questions because I've been really having fun with them, and I feel a lot more connected to the team. Like, I just get to know them more as people and the things they're interested in, and what they do in their free time. So, yeah, highly recommend adding a fun question to your daily syncs.

MINA: Yeah, we started doing that on Mission Control at our team sync meetings recently, too, where the first person...we actually have an order generator that somebody on the team wrote where it takes everyone's first and last name and scramble them and then randomizes the order. So you kind of have to figure out where in the queue you are and who's coming up next after you. But the first person that goes in the queue every day has to think of an icebreaker question.

STEPHANIE: That's kind of a lot of pressure [laughs] for a daily meeting, especially if you're having to unscramble names and then also come up with the icebreaker question. I personally would be very stressed [laughs] by that. But I also can see that it's...I also think it's very fun, especially for a small team like yours.

MINA: Yeah, yeah, just seven of us; we get to know really well what letters are in everyone's names. But I was first today, and I didn't have an icebreaker question ready. So I ended up just passing. So that's also an option.

STEPHANIE: That's fair. Maybe I'll link you to our random question generator, so you can find some inspiration. [laughs]

MINA: Yeah, it's a ChatGPT situation.

STEPHANIE: So you mentioned that you and I had just been traveling together for two weeks. And that's because Mina and I were at RubyKaigi in Matsumoto, Japan, earlier this May. And that's the topic of today's episode: Our Experience at RubyKaigi. And the really cool thing that I wanted to mention was that this was all possible because Mina and I were sponsored by WNB.rb, which is a global community of women and non-binary people working in Ruby. And I've mentioned this group on the show before, but I wanted to plug it again because I think that this was something really special that we got to do.

WNB runs a lot of initiatives, like, meetups and panels supporting people to speak at conferences and book clubs. And, you know, just many different programming events for supporting women and non-binary Rubyists in their career growth. And they are recently beginning a new initiative to sponsor folks to attend conferences. And Mina, you and I were the first people to get to try this out and go to an international conference. So that was really awesome. It was something that I don't think I would have done without the support from WNB.

MINA: And you almost didn't do. I think there was a lot of convincing [chuckles] that went on at the beginning to kind of get you to, like, actually consider coming with me.

STEPHANIE: It's true. It's true. I think you had DMed me, and you were, like, so, like, RubyKaigi, like, eyeball emoji. [laughs] I was, I think, hesitant because this was my first international conference. And so there was just a lot of, like, unknowns and uncertainty for me. And I think that's going to be part of what we talk about today. But is there anything that you want to say about WNB and how you felt about being offered this opportunity?

MINA: Yeah. When Emily and Jemma, the founders of WNB, approached us with this opportunity and this offer, I think I was...taken aback is not really quite the right words but, like, surprised and honored, really, I think it's a better word. Like, I was very honored that they thought of us and kind of took the initiative to come to us with this offer.

So I'm really grateful for this opportunity because going to RubyKaigi, I think it's always something that was on my radar. But I never thought that...well, not never. I thought that I had to go as a speaker, which would have been, like, a three to five-year goal. [laughs] But to be able to go as an attendee with the support of the group and also of thoughtbot was really nice.

STEPHANIE: Yeah, absolutely. That investment in our professional development was really meaningful to me. So, like you, I'm very grateful. And if any of our listeners are interested in donating to WNB.rb and contributing to the community's ability to send folks to conferences, you can do so at wnb-rb.dev/donate. Or, if you work for a company that might be interested in sponsoring, you can reach out to them at organizers@wnb-rb.dev.

MINA: I highly recommend doing that.

STEPHANIE: So, one of the questions I wanted to ask you about in terms of your RubyKaigi experience was, like, how it lined up with your expectations and if it was different or similar to what you were expecting.

MINA: Yeah, I have always heard that when people talk about RubyKaigi as a conference and about its contents, the word that everyone uses to describe it is technical. I have already had sort of a little bit of that expectation going in. But I think my interpretation of the word technical didn't really line up with how actually technical it was. And so that was one thing that was different than what I had expected.

STEPHANIE: Could you elaborate on what was surprising about the way that it was technical?

MINA: Yeah. I think that when I hear technical talks and having been to some Ruby and Rails confs here in the States, when I hear about technical talks, it's a lot more content about people using the technology, how they use Ruby to do certain things, or how they use Rails to achieve certain goals in their day-to-day work or side projects. But it seems at RubyKaigi; it is a lot more about the language itself, how Ruby does certain things, or how interpreters implement Ruby, the language itself. So I think it's much more lower-level than what I was expecting.

STEPHANIE: Yeah, I agree. I think you and I have gone to many of Ruby Central conferences in the U.S., like RubyConf and RailsConf. So that was kind of my comparison as well is that was, you know, the experience that I was more familiar with. And then, going into this conference, I was very surprised that the themes of the talks were, like you said, very focused on the language itself, especially performance, tooling, the history and future of Ruby, which I thought was pretty neat.

Ruby turns 30, I think, this year. And one thing that I noticed a lot was folks talking about using Ruby to reflect on itself and the possibilities of utilizing those capabilities to improve our experience as developers using the language.

MINA: Yeah. I think one of the things I was really fascinated by is...you had mentioned the performance. There were several talks about collecting how Ruby performs at certain levels. And I thought that that was quite interesting and things I had never thought about before, and I'm hoping to think about in the future. [laughs]

STEPHANIE: Yeah. One talk that I went to was Understanding the Ruby Global VM Lock by Ivo Anjo. And that was something that, you know, I had an awareness of that Ruby has this GVL and certain...I had, like, a very hand-wavy understanding about how, like, concurrency worked with Ruby because it hasn't been something that I've really needed to know too deeply in my day-to-day work. Like, I feel a little bit grateful not to have run into an issue where I had to, you know, dive deep into it because it was causing problems. [laughs]

But attending that talk was really cool because I liked that the speaker did give, like, an overview for folks who might be less familiar but then was able to get really deep in terms of, like, what he was doing workwise with improving his performance by being able to observe how the lock was being used in different threads and, like, where it might be able to be improved. And he shared some of his open-source projects that I'll link in the show notes.

But, yeah, that was just something that I was vaguely aware of and haven't yet, like, needed to know a lot about, but, you know, got to understand more by going to this conference. And I don't think I would have gotten that content otherwise.

MINA: Yeah, I agree. The talk that you are referencing is one of my favorite as well. I think, like you, kind of this vague idea of there's things going on under the hood in Ruby is always there, but to get a peek behind the curtain a little bit was very enlightening. I wrote down one of the things that he said about how highly optimized Ruby code can still be impacted and be slow if you don't optimize GVL. And he also shared, I think, some strategies for profiling that layer in your product, if that is something you need, which I thought was really cool.

STEPHANIE: Yeah. I think I had mentioned performance was a really big theme. But I didn't realize how many levers there were to pull in terms of the way Ruby is implemented or the way that we are able to use Ruby that can improve performance. And it's really cool to see so many people being experts at all of those different components or aspects of making Ruby fast. [laughs]

MINA: Yeah. I think that part of the work that we do on Mission Control is monitoring performance and latency for our clients. And while I don't expect having to utilize some of the tools that I learned at RubyKaigi, I expect being aware of these things helping, I think, in the long run.

STEPHANIE: Yeah, absolutely. Joël and I have talked on the show about this idea of, like, push versus pull learning. So push, being you consume content that may not be relevant to you right now but maybe will be in the future. And you can remember, like, oh, I watched a talk on this, or I read something about this, and then you can go refer back to it.

As opposed to pull being, like, I have this thing that I don't understand, but I need to know right now, so I'm going to seek out resources about it. And I think we kind of landed on that both are important. But at Kaigi, especially, this was very much more push for me where there's a lot of things that I now have an awareness of.

But it's a little different, I think, from my experience at Ruby Central conferences where I will look at the schedule, and I will see talks that I'm like, oh, like, that sounds like it will be really relevant to something I'm working through on my client project or, like, some kind of challenging consulting situation.

And so the other thing that I noticed that was different was that a lot of the U.S. conferences are more, I think like business and team challenges-focused. So the talks kind of incorporate both a technical and socio-cultural aspect of the problems that they were solving. And I usually really like that because I find them very relatable to my day-to-day work. And that was something that was less common at Kaigi.

MINA: Also, that I've never been to a conference that is more on the academic side of things. So I don't know if maybe that is more aligned with what Kaigi feels like.

STEPHANIE: Yeah, that's true. I think there were a lot of talks from Ruby Committers who were just sharing, like, what they've been working on, like, what they've been thinking about in terms of future features for Ruby. And it was very much at the end of those talks, like, I'm open to feedback. Like, look out for this coming soon, or, like, help contribute to this effort.

And so it was interesting because it was less, like, here are some lessons learned or, like, here are some takeaways, or, like, here's how we did this. And more like, hey, I'm, you know, in the middle of figuring this out, and I'm sharing with you where I'm at right now. But I guess that's kind of the beauty of the open-source community is that you can put out a call for help and contributions.

MINA: Yeah, I think they call that peer review in the academic circles.

STEPHANIE: [laughs] That's fair.

MINA: [laughs]

STEPHANIE: Was there anything else that you really enjoyed about the conference?

MINA: I think that one of my favorite parts, and we've talked about this a little bit before, is after hours on the second day, we were able to connect with Emori House and have dinner with their members. Emori House is a group that supports female Kaigi attendees specifically. I think it's that they, as a group, rent out an establishment or a house or something, and they all stay together kind of to look out for each other as they attend this very, I think, male-dominated conference.

STEPHANIE: Yeah. I loved that dinner with folks from Emori House too. I think the really cool thing to me is that it's just community and action, you know, like, someone wanted to go to this conference and make it easier for other women to go to this conference and decided to get lodging together and do that work of community building. And that social aspect of conferences we hadn't really talked about yet, but it's something that I really enjoy. And it's, like, one of the main reasons that I go to conferences besides learning.

MINA: Yeah, I agree. At the Ruby Central conferences, one of my favorite parts is always the hallway track, where you randomly meet other attendees or connect with attendees that you already knew. And like I mentioned, this dinner with Emori House happened on the second night. And I think by midday second day; I was missing that a little bit. The setup for RubyKaigi, I noticed, does not make meeting people and organizing social events as easy as I had been used to, and part of that, I'm sure, is the language barrier.

But some places where I had met a lot of the people that I call conference friends for Ruby Central conferences had been at the lunch table. And Kaigi sets up in a way where they send you out with food vouchers for local restaurants, which I thought was really cool. But it doesn't make meeting people and organizing groups to go out together with people you don't already know a little more difficult. So meeting Emori House on the second night was kind of exactly what I had been missing at the moment.

STEPHANIE: Yeah, agreed. I also really thrive off of more smaller group interactions like organically, you know, bumping into people on the hallway track, ideally.

I also noticed that, at Kaigi, a lot of the sponsors end up hosting parties and meetups after the conference in the evenings. And so that was a very interesting social difference, I think, where the sponsors had a lot more engagement in that sense. You and I didn't end up going to any of those drink-ups, are what they're called.

But I think, similarly, if I were alone, I would be a little intimidated to go by myself. And it's kind of one of those things where it's like, oh, if I know someone, then we can go together. But, yeah, I certainly was also missing a bit of a more organic interaction with others. Though, I did meet a few Rubyists from just other places in East Asia, like Taiwan and China. And it was really cool to be in a place where people are thinking about Ruby differently than in the U.S.

I noticed in Japan; there's a lot more energy and enthusiasm about it. And, yeah, just folks who are really passionate about making Ruby a long-lasting language, something that, you know, people will continue to want to work with. And I thought that was very uplifting because it's kind of different from what the current industry in the U.S. is looking like in terms of programming languages for the jobs available.

MINA: It's really energizing, I think, to hear people be so enthusiastic about Ruby, especially, like you said, when people ask me what I do here, I say, "Developer," and they say, "Oh, what language do you work in?" I always have to be kind of like, "Have you heard of Ruby?" [laughs] And I think it helps that Ruby originated in Japan. They probably feel a little bit, like, not necessarily protective of it, but, like, this is our own, and we have to embrace it and make sure that it is future-facing, and going places, and it doesn't get stale.

STEPHANIE: Right. And I think that's really cool, especially to, you know, be around and, like, have conversations about, like you said, it's very energizing.

MINA: Yeah, like you mentioned, we did meet several other Rubyists from, like, East Asian countries, which doesn't necessarily always happen when you attend U.S.-based or even European-based conferences. I think that it is just not as...they have to travel from way farther away. So I think it's really cool to hear about RubyConf Taiwan coming up from one of the Rubyists from Taiwan, which is awesome. And it makes me kind of want to go. [laughs]

STEPHANIE: Yeah, I didn't know that that existed either. And just realizing that there are Rubyists all over the world who want to share the love of the language is really cool. And I am definitely going to keep a lookout for other opportunities. Now that I've checked off my first international conference, you know, I have a lot more confidence about [laughs] doing it again in the future, which actually kind of leads me to my next question is, do you have any advice for someone who wants to go to Kaigi or wants to go to an international conference?

MINA: Yeah, I think I have both. For international conferences in general, I thought that getting a buddy to go with you is really nice. Steph and I were able to...like, you and I were able to kind of support each other in different ways because I think we're both stressed [laughs] about international travel in different ways. So where you are stressed, I'm able to support, and where I'm stressed, you're able to support. So it was really nice and well-rounded experience because of that.

And for RubyKaigi specifically, I would recommend checking out some of the previous year's talks before you actually get there and take a look at the schedule when it comes out. Because, like we said, the idea of, I think, technical when people use that word to describe the content at RubyKaigi is different than what most people would expect. And kind of having an idea of what you're getting into by looking at previous videos, I think, will be really helpful and get you in the right mindset to absorb some of the information and knowledge.

STEPHANIE: Yeah, absolutely. I was just thinking about...I saw in Ruby Weekly this week Justin Searls had posted a very thorough live blogging of his experience at Kaigi that was much more in the weeds of, like, all of the content of the talks. And also had tips for how to brew coffee at a convenience store in Japan too. So I recommend checking that out if folks are curious about...especially this year before the videos of the talks are out.

I think one thing that I would do differently next time if I were to attend Kaigi or attend a conference that supports multiple languages...so there were talks in Japanese and English, and the ones in Japanese were live interpreted. And you and I had attended, like, one or two, but it ended up being a little tough to follow because the slides were a little bit out of sync with the interpretation.

I definitely would want to try again and invest a little more into attending talks in Japanese because I do think the content is still even different from what we might be seeing in English. And now that I know that it takes a lot of mental energy, just kind of perhaps loading up on those talks in the morning while I'm still, you know --

MINA: [laughs]

STEPHANIE: Fresh-faced and coffee-driven. [laughs] Rather than saving it for the afternoon when it might be a little harder to really focus.

MINA: I think my mental energy has a very specific sweet spot because definitely, like, late in the afternoon would not be good for that. But also, like, very early in the morning would also not be very good for that because my coffee hasn't kicked in yet.

STEPHANIE: That's very real as well.

MINA: Do you think that there is anything that the conference could have done to have made your experience a little tiny bit better? Is there any support that you could have gotten from someone else, be it the conference, or WNB, or thoughtbot, or other people that you had gone with that could have enhanced this experience?

STEPHANIE: Hmm, that's an interesting question. I'm not really sure because I was experiencing so many new things --

MINA: [laughs]

STEPHANIE: That that was kind of, like, what was top of mind for me was just getting around even just, like, looking at all the little sponsor booths because that was, like, novel for me to see, like, different companies that I've never heard of before that I think when I asked you about expectations earlier, like, I actually came in with not a lot of expectations because I really was just open to whatever it was going to be.

And now that I've experienced it once, I think that I have a little more of an idea of what works for me, what I like, what I don't like. And so I think it really comes down to it being quite a personal experience and how you like to attend conferences and so --

MINA: For sure.

STEPHANIE: At the end of the day, yeah, like, definitely recommend just going if that opportunity is available to you and determining for yourself how you want that experience to be.

MINA: Certainly. I think just by being there you learn a lot about what you like in conferences and how we like to attend conferences. On a personal level, I'm also an organizer with Ruby Central with their scholarship committee. And that's somewhere where we take new Rubyists or first-time conference attendees and kind of lower the barrier for them to attend these conferences. And the important part I wanted to get to is setting them up with a mentor, somebody who has attended one of these conferences before that can kind of help them set goals and navigate. And I thought that someone like that would...at RubyKaigi, being both our first times, might be useful.

STEPHANIE: Yeah, absolutely. I think that's totally fair. One thing I do really like about the Ruby Central conferences is the social support. And I think you had mentioned that maybe that was the piece that was a little bit missing for you at this conference.

MINA: Yeah. I know that someone had asked early on, I think, like, the night before the conference officially kicked off, whether there is a Slack or Discord space for all conference attendees so that people can organize outings or meals. And that is definitely something that at least the Ruby Central conferences have, and I imagine other conferences do too, that was missing at Kaigi as well.

STEPHANIE: I'm wondering if you would go to Kaigi again and maybe be that mentor for someone else.

MINA: I think so. I think I had different feelings about it when we were just leaving the conference, kind of feeling like some of these things that I'm learning here or that I'm being made aware of rather at RubyKaigi will come up important in the future, but maybe not right away. So then I was kind of walking away with a sense of, like, oh, maybe this is a conference that is important, but I might deprioritize if other opportunities come up.

But then I started to kind of, like, jot down some reflections and retroing with myself on this experience. And I thought what you mentioned about this being the sort of, like, the push learning opportunity is really nice because I went in there not knowing what I don't know. And I think I came out of it at least being a little bit aware of lots of things that I don't know.

STEPHANIE: Yeah, yeah. Maybe, like, what I've come away with this conversation is that there is value in conferences being different from each other, like having more options. And, you know, one conference can't really be everything for everyone. And so, for you and I to have had such a very different experience at this particular conference than we normally do, that has value. It also can be something that you end up deciding, like, you're not into, and then you know. So, yeah, I guess that is kind of what I wanted to say about this very new experience.

MINA: Yeah, having new experiences, I think, is the important part. It's the same idea as you want to get a diverse group of people in the room together, and you come out with better ideas or better products or whatever because you have other points of view. And I think that attending conferences, even if not around the world, that are different from each other either in academia or just kind of, like, branching out of Ruby Central conferences, too, is a really valuable experience. Maybe conferences in other languages or language-agnostic conferences.

STEPHANIE: Yeah, well said. On that note, shall we wrap up?

MINA: Let's do it.

STEPHANIE: Show notes for this episode can be found at bikeshed.fm.

JOËL: This show has been produced and edited by Mandy Moore.

STEPHANIE: If you enjoyed listening, one really easy way to support the show is to leave us a quick rating or even a review in iTunes. It really helps other folks find the show.

JOËL: If you have any feedback for this or any of our other episodes, you can reach us @_bikeshed, or you can reach me @joelquen on Twitter.

STEPHANIE: Or reach both of us at hosts@bikeshed.fm via email.

JOËL: Thanks so much for listening to The Bike Shed, and we'll see you next week.

ALL: Byeeeeeeeeee!!!!!!!!!!

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