Fabian GiesenOct 4, 2023

"OMG it's a 25GB game patch, must be tons of amazing new content that they're keeping quiet about."

*Could* be, sure, and stealth launches are a thing sometimes, but generally speaking, if it's a big patch for no discernible reason not attached to anything upcoming that's already been announced, the actual reason is probably something very boring and usually non-game-related

Show threadFabian GiesenOct 4, 2023

(Very) incomplete list of reasons for big patches that are completely unrelated to new content, from personal experience:

- Somebody added an extra field to some header somewhere, so everything that comes after the header moves and has slightly different context, plus content chunking puts chunk boundaries in different places now, so all the compressed data after changes
- We updated compilers and our assets are built using fast math, YOLO

Show threadFabian GiesenOct 4, 2023
- Sound assets use Opus in float (not fixed-point) mode which uses RCPSS/RSQRTSS during encode, and we switched our build machines between Intel and AMD, so presto, new audio for everyone
- we changed audio codecs
- we changed lossless data codecs for some or all data
- we changed _something_ and don't know for sure what or why it's a 15GB patch but we only noticed 4 days before cert and it was too scary to figure out and fix before then, so here's hoping it's fine
Show threadFabian GiesenOct 4, 2023
- this one simple bugfix in our vector math library had bigger ripple effects than we thought
- this one simple bugfix in the platform libm had bigger ripple effects than we thought
- this one simple bugfix in our compiled asset caching had bigger ripple effects than we thought
- who are we kidding, past a certain scale there's really no such thing as a simple bugfix
Show threadFabian GiesenOct 4, 2023
- given all of the above, reproducible asset builds are Actually Hard, therefore we use content-addressed storage and just cache build artifacts... unfortunately something went wrong and corrupted that store so we had to rebuild everything and this is what happened
Show threadFabian Giesen
(TFW what you thought was just a transient local cache is actually a load-bearing persistent data store that it was never designed to be)
Oct 4, 2023 at 9:57pmWeb
Show threada kilo of saucepans (rakslice)Oct 4, 2023
@rygorous 👻
Show threadLeszek GodlewskiOct 4, 2023
@rygorous that is oddly specific. Would you be referring to something with a 3-letter acronym that starts with a D, ends with a C, and has a D in the middle, that typically runs on Windows shares?
Show threadFabian GiesenOct 4, 2023
@TheIneQuation DDC is one example (although FWIW we don't generally run this on Windows shares at Epic), but I've also built one of these myself (15 years ago at the company I was at at the time) and interacted with multiple RAD customers who also had versions of this, all fairly similar in big picture terms
Show threadLeszek GodlewskiOct 5, 2023
@rygorous surely you mean "not anymore"? 🙂 I distinctly recall DefaultEngine.ini with site-specific UNC addresses. 🙃 But that was 5+ years ago, admittedly.
Show threadrfOct 4, 2023
@rygorous In a totally different context I recently spent hours to keep a cache that was no longer just a cache from getting cleared. Ah, the beautiful, elegant, exact science of computing! 😭
Show threadBenji SmithOct 4, 2023
@rygorous A couple jobs back, the studio I was working at started having our nightly clean build fail, though everyone's workstations and the normal CI build were fine. Turns out we had either moved some file, or changed something in the build so a particular object file was no longer getting rebuilt, but was still cached for any iterative builds. So until we fixed it, everyone's workspace was on a ticking timebomb that would blow up when they ran a clean build