I suspect that this limit was just the Max value of whatever number format they were using was. The chances of it not really being 65536 are fairly low. Its just too coincidental.
Except it's not 65536 -- it's 65356. (I just verified in the PDF.)
Which actually makes me wonder if somebody fat-fingered it and meant to type 65536 by hand and got it wrong. Which given everything we've found out about the sloppiness there, would seem quite apropos.
Normally I wouldn't think so, but the trailing "999994" also just seems so strangely floating point-derived... but who even knows.
So people are guessing what the number is from, I will guess too. I never really worked at ftx you guys. It's a work of parody etc.
> be me
> new employee at ftx bahamas office
> sbf is busy in dc doing effective altruism
> polycule ppl just got text from him
> tfw not in polycule
> sbf got a text from caroline
> we have to double alameda's credit line again
> guess that's my job now
> open excel spreadsheet
> they are planning to convert it to python soon
> find "borrow" column
> dozens of accounts have millions of dollars of credit
> find the alameda borrow entry
> feels goodman.jpg
> 32678000000e-3
> wtf is that
> it's 32678000000 mils divided by a thousand
> a mil is a tenth of a cent, it's finance jargon used by exchanges
> the e-3 at the end is scientific notation to divide by a thousand
> $32,678,000
> they've been doubling it by hand while high on stimulants
> last time they mixed up the 6 and 7
> bigbraintime.png
> i can just put parentheses around it and multiply by two
> leave it like that in the excel cell
> 32678000000e-3
> (32678000000-3)*2
> sbf texted again he says we solved caroline's problem
> success.png
> $65,355,999,994
The author of that comment was incorrect though. Page 18 of the PDF shows that it was an arbitrarily hardcoded number encoded in a BigDecimal, has nothing to do with 16 bit integers. Furthermore the limit was 65*3*55... whereas the max 16-bit unsigned integer is 65*5*35, so the digits don't even match up.
It's a cool hypothesis, and perhaps the person who hardcoded that number was even inspired by 2^16 - 1 in some way, but as the replies point out it doesn't really make much sense beyond an odd curiosity.
If you want to say what you think is important about an article, that's fine, but do it by adding a comment to the thread. Then your view will be on a level playing field with everyone else's: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&so...
You're overthinking it and in fact AWS has a bunch of security stuff (HSM, secure enclave, etc) that makes it extra attractive. For reference, Stripe (which isn't FTX but it's Fintech and handles large amounts of money) uses AWS for their environment. If you're asking if there's some secret hidden AWS region FTX was using, why would they bother? The known special region, GovCloud, is a couple years behind the other regions in features. Also from what's been publicly revealed, FTX isn't exactly the shining example of the finest possible engineering.
Nobody on Twitter had any good ideas. However Jon Callas suggested it might be a Singapore phone number, which was the best suggestion I saw ;) I even called it (it’s one digit too long) and got an error message.
That’s just a limit in their risk system not a judgement of any real scale. Better to read it as “infinity” because the point of the setting was to remove any real limit.
You're asumming the final number id managed by a sole number. Maybe there a "size" value and a "quantity" value.
An example would be a float representing the final magnitude over the base magnitude (i.e. thousands of dollars), and the base quantity of thosands of dollars an unsinged 16bit integer.
It would be a commonly considered weird approach (you could/should use Decimal types for money), but hey, the final number is strangely near to be such a typical number (2^16).
PS: Like a sibling suggested, other hypothesis is that maybe it was something akin to a bare napkin calculation/decision made by humans (with human errors) eventually digitalized.
