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Jane Street and the OCaml Compiler (2018) [video]

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Re: Jane Street and the OCaml Compiler (2018) [video]

#41

Post by asveikau »

lend000 wrote: post #21
throwaway992293 wrote: post #17

Earlier quoted context omitted.

I have no doubt that a Sanders presidency would have a negative effect on Wall Street profits (which is why you see people like Ron giving millions of dollars to prevent it) but that's hardly a measure of the health of "the economy."

Perhaps you misunderstood what I said by long-biased, but companies like Jane Street, Two Sigma, RenTech will be just fine (and will probably adapt better than most) to structural changes and a decline in growth of the economy. The tax rates will hit individuals, but probably not as much as his donation set him back, so it's almost certainly ideological. Clearly you are passionate about Sanders, and that's fine, but…

It's strange to me that you seem to assume higher taxes on top earners (which is probably the conclusion I parse out of Sanders and his proponents, though they would face opposition in Congress to get there) necessarily means that economic growth will decline. Speaking historically, the United States has gone through periods of high growth with top marginal tax rates at something like 90%.

Re: Jane Street and the OCaml Compiler (2018) [video]

#42

Post by AllanHoustonSt »

ironSkillet wrote: post #38
AllanHoustonSt wrote: post #30

Earlier quoted context omitted.

As others have mentioned, they have ways of writing OCaml specifically to not trigger the GC or perform any excessive allocations. Helps when you have your own version of the compiler and a branch of the language itself. This is talked about with an example in this talk around 18m30s: https://www.youtube.com/watch?v=BysBMdx9w6k Also as someone else mentioned, Jane Street doesn't try regularly competing (to my knowled…

I feel like the jane street tech blog has exceptionally good quality, with a really nice mix of academic and practical ideas thrown in. Do you happen to know of any other video series with this kind of exposition?

Unfortunately I agree with you Jane Street's tech blog and published lecture series are great and probably the best I know of. They make for great advertising to boot. Lecture series like Jane Street's are common in larger trading firms (more than 100-150 headcount) but I haven't seen one of JS' caliber yet.

If you welcome general corporate blogs, I think Google AI's technical blog is quite good. Their frequent publications on distributed computing strike a good balance of academic and practical ideas:

https://ai.googleblog.com

Cloudflare also has one of my favorite more engineering focused blogs.

Re: Jane Street and the OCaml Compiler (2018) [video]

#43

Post by lend000 »

asveikau wrote: post #41
lend000 wrote: post #21

Earlier quoted context omitted.

Perhaps you misunderstood what I said by long-biased, but companies like Jane Street, Two Sigma, RenTech will be just fine (and will probably adapt better than most) to structural changes and a decline in growth of the economy. The tax rates will hit individuals, but probably not as much as his donation set him back, so it's almost certainly ideological. Clearly you are passionate about Sanders, and that's fine, but…

It's strange to me that you seem to assume higher taxes on top earners (which is probably the conclusion I parse out of Sanders and his proponents, though they would face opposition in Congress to get there) necessarily means that economic growth will decline. Speaking historically, the United States has gone through periods of high growth with top marginal tax rates at something like 90%.

Higher taxes are not the only economics implications of a Sanders presidency, especially when you look at some of the governments Sanders has praised over his career. A better tax structure is necessary and the easiest thing to do, but I don't trust Sanders to figure that out. Even Warren comes up with a wealth tax instead of just fixing the income and capital gains tax brackets.

Hint: add three more brackets with 4mm+ at 50%, 20mm+ at 65% and 100mm+ at 80% and do the same relative adjustments for capital gains. No need for the government to seize the means of production when you haven't tried the obvious thing. Our current tax brackets are a joke, topping out around 500k when some people make 10,000 times that.

Re: Jane Street and the OCaml Compiler (2018) [video]

#44

Post by insulanian »

helsinki wrote: post #10
tartoran wrote: post #9

Earlier quoted context omitted.

Why C++ now but not then, 20+ years ago? And would F# be suitable for the task? Im genuinely interested

Presumably Jane Street didn’t choose C++ because they wanted to reduce bugs introduced by the preservation of state; the killer of prop shops. F# was developed six years after their founding, hence too young, and more importantly, a Microsoft-owned clone of OCaml. I don’t think it even ran on Linux before 2015. Today, F# might just suit the job, assuming you are open to being locked into the .NET family. An interesti…

> assuming you are open to being locked into the .NET family

Which is not different than being locked into e.g. JVM family, or even being locked into OCaml itself.

Re: Jane Street and the OCaml Compiler (2018) [video]

#45

Post by tianyicui »

ironSkillet wrote: post #35
codingslave wrote: post #33

Seems to me that firms like two sigma and jane street form some sense of "mystique" about them with regards to how elite their developers are. But once you get inside, most people are writing run of the mill software. Google has the same tactic, even paying below market rates to people willing to work their for the brand. Jane Street does pay very well, but still, most of their hiring is based off of prestigious coll…

With so much money on the line, hedge funds and other trading firms focus a lot of effort on marketing and building up a perception that they truly are something special (at least those that take outside client money). Internally, things could be rather mundane, and even downright awful (from a technology perspective). Not commenting on Jane Street in particular, just the industry in general. Source: I've worked at a…

FWIW, Jane Street is not a hedge fund nor take outside client money.

(Edit: I work at Jane Street.)

Re: Jane Street and the OCaml Compiler (2018) [video]

#46

Post by dnautics »

matlin wrote: post #7
smabie wrote: post #2

i asked this question at my Jane Street interview, but never got a real answer: how does a market making latency arb firm handle GC pauses that are inherent with any GC language? OCaml is better in this regard than, say, the JVM, but it still seems problematic. I know they wrote some FPGA compiler stuff with OCaml, but I can't imagine that all of their execution is running through FPGAs. Even if it's possible, it see…

In Elixir/Erlang there is no global pausing for garbage collection, instead each process is individual garbage collected. And I remember hearing about a strategy that allows you to avoid it entirely by ensuring your process's lifetime is short enough (or heap size big enough) that it basically never happens despite the BEAM (Erlang VM) running with garbage collection. Edit: my point is that it is likely avoidable thr…

This is only possible due to the way that the BEAM VM and its languages are architected; the gc itself is "not the smartest", but it doesn't have to be because there is no shared memory and process boundaries are failure domains.

Re: Jane Street and the OCaml Compiler (2018) [video]

#47

Post by quickthrower2 »

ironSkillet wrote: post #35
codingslave wrote: post #33

Seems to me that firms like two sigma and jane street form some sense of "mystique" about them with regards to how elite their developers are. But once you get inside, most people are writing run of the mill software. Google has the same tactic, even paying below market rates to people willing to work their for the brand. Jane Street does pay very well, but still, most of their hiring is based off of prestigious coll…

With so much money on the line, hedge funds and other trading firms focus a lot of effort on marketing and building up a perception that they truly are something special (at least those that take outside client money). Internally, things could be rather mundane, and even downright awful (from a technology perspective). Not commenting on Jane Street in particular, just the industry in general. Source: I've worked at a…

Is the sausage made in VBA?

Re: Jane Street and the OCaml Compiler (2018) [video]

#48

Post by asveikau »

lend000 wrote: post #43
asveikau wrote: post #41

Earlier quoted context omitted.

It's strange to me that you seem to assume higher taxes on top earners (which is probably the conclusion I parse out of Sanders and his proponents, though they would face opposition in Congress to get there) necessarily means that economic growth will decline. Speaking historically, the United States has gone through periods of high growth with top marginal tax rates at something like 90%.

Higher taxes are not the only economics implications of a Sanders presidency, especially when you look at some of the governments Sanders has praised over his career. A better tax structure is necessary and the easiest thing to do, but I don't trust Sanders to figure that out. Even Warren comes up with a wealth tax instead of just fixing the income and capital gains tax brackets. Hint: add three more brackets with 4m…

> especially when you look at some of the governments Sanders has praised over his career.

Can you be more specific here?

I mean, there can be praise for some governments without saying we advocate for everything they do. It's possible for instance to praise Cuba for health care outcomes without wanting to become Fidel Castro. There are also some ridiculous insinuations that Sanders is some kind of Chavista, which to me is a bit of a flag that someone isn't serious about their anti-Sanders discussion. I would say he advocates for more of a European type of safety net.

> No need for the government to seize the means of production

I do not believe Sanders proposes that.

Re: Jane Street and the OCaml Compiler (2018) [video]

#49

Post by nimchimpsky »

imglorp wrote: post #8
Reelin wrote: post #5

Earlier quoted context omitted.

I'm not entirely clear on the use case, but Disruptor by LMAX Exchange is for the JVM and seems very concerned with latency. ( https://github.com/LMAX-Exchange/disruptor/wiki/Performance-... )

Here's the backstory, worth a good read in general. https://martinfowler.com/articles/lmax.html I suspect at least one use case has gone away since the Fowler wrote that: wanting to saturate the write channel into a database in general. Consistent hashing document DBs like DynamoDB, Cassandra, etc. are basically infinitely scalable for writes. It's not clear to me if LMAX still makes sense if you want to assemble the…

"wanting to saturate the write channel into a database in general. Consistent hashing document DBs like DynamoDB, Cassandra, etc. are basically infinitely scalable for writes."

I don't really understand what are you are saying there ?

But we use disruptors for processing millions of messages/events as quickly as possible, with a variety of different consumers.

Re: Jane Street and the OCaml Compiler (2018) [video]

#50

Post by hermitdev »

ironSkillet wrote: post #35
codingslave wrote: post #33

Seems to me that firms like two sigma and jane street form some sense of "mystique" about them with regards to how elite their developers are. But once you get inside, most people are writing run of the mill software. Google has the same tactic, even paying below market rates to people willing to work their for the brand. Jane Street does pay very well, but still, most of their hiring is based off of prestigious coll…

With so much money on the line, hedge funds and other trading firms focus a lot of effort on marketing and building up a perception that they truly are something special (at least those that take outside client money). Internally, things could be rather mundane, and even downright awful (from a technology perspective). Not commenting on Jane Street in particular, just the industry in general. Source: I've worked at a…

Also having worked for a hedge fund, they're generally going to do their best to get you at the lowest salary possible. The overall benefits might be good, but they're going to do their best to low ball on the salary, "you'll make it up at bonus time!" Bullshit, You have to negotiate with hedge funds and be willing to walk away from a shit offer. I started at one a year out of college. Made 3x what I did as an intern. I was happy, at first. You can budget around a salary for rent, utilities, etc. You can't budget hoping for a bonus to make ends meet.

Took me about 3 years to realize I was being paid half of my coworkers doing the same to lesser jobs as mine. Took me resigning with an offer in hand for twice what I was making before they upped their offer. I stayed for another 3 years before I got so fed up with the bullshit I actually left for a lower paying job (also less stress).

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