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Comment by oneloop | Hacker News Reader

Also, wasn't there a ridiculous issue that they had where the db can't be bigger than 4gb on a 32 bit file system because that's the largest size a file can have...?

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Yes, apparently the limit on 32-bit is 2GB actually. MongoDB has always stated upfront that 32-bit architectures are not recommended for production use for precisely this reason: http://blog.mongodb.org/post/137788967/32-bit-limitations

This has also has been stated on their download page for 32-bit binaries as well.

It hasn't always been stated there, and it was a warning on a README somewhere. The server would run happily on 32 bits, and never crash or produce any user-visible errors, it would just silently corrupt data while pretending the insertion went great.

And that's the real issue I would think. If it shut itself down or went into read-only and generated errors it wouldn't be so bad. The limitations 32-bit architectures are why we have 64bit architectures. I think it's fair as a developer to require x64 instead of jumping through hoops to support both architectures. But if you're going to release 32-bit binaries for something like development or testing you should be explicit about the use cases and limitations and avoid failing silently when they're exceeded.

This stems from their choice of "mmap and done" as their entire IO strategy, for earlier versions. The data loss is silly though and shows their attitude.

Oracle 9 on 32 bit can handle 32GiB databases without any issue, and bigger setup to use more that a single file per table space. And Oracle 9 it's old.

Note: I hate Oracle DB, but I must work with Oracle 9/10/11/2 DBs because is what our clients have.

> When running a 32-bit build of MongoDB, the total storage size for the server, including data and indexes, is 2 gigabytes. For this reason, do not deploy MongoDB to production on 32-bit machines.

From https://docs.mongodb.com/manual/installation/#faq-32-bit-lim...

There was also the issue where errors were either logged or not, based on the result of Math.random(): http://stackoverflow.com/q/16833100/1233508

While I don't care about mongoDB, who's running 32bit anymore? And for a production DB?

DB exist on more than servers, e.g. in an embedded environment... You find sqlite in the oddest places... One could imagine finding mongodb there too, with bonus data corruption...

Spain public administrations.

For example, the 32 bit mongoDB instance that's managing a grand total of 2 wifi access points here.

Umm... Wow, mongo. Boy, am I glad I didn't decide to pick you.

Let's get some statistics. MySQL and Postgres both have and undefined max DB size, and max table sizes upwards of 16 and 32 TB, respectively.

SQLite has no max table size I could find, but had a max DB size of 140 TB. 140TB. And this is from a database that reccomends not using it if your data grows too large.

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