3 ms·

In my experience with several Bazel projects, when everything works, it's great. But, the case where it doesn't work are way more painful than anything I've en

In my experience with several Bazel projects, when everything works, it's great. But, the case where it doesn't work are way more painful than anything I've encountered from CMake + (make, ninja). Bazel is basically pathologically bad about resource use - if you run out of anything (CPU, memory, disk, inodes) you're totally hosed and probably have to reset the machine. Bazel caching is great, but boy do you pay for it in disk space - the bazel cache on my machine, for a reasonable (but by no means huge) monorepo is probably more than 100GB, and because it absolutely loves creating symlinks to everything it's very easy to run out of inodes on smaller disks even when there's plenty of space otherwise available. Bazel basically feels like the "GC language" of build systems - it behaves like there's nearly infinite resources available and so long as that illusion can be maintained, all is well. For reference, the machines I'm using are plenty beefy (several AMD 16C/32T + 128GB ram + 1TB nvme, and several Intel 28C/56T) - it's really inexcusable that a build system makes the machine hang.

0xFFC 6y ago
Just curious, what specific project do you compile so that you ran out of resources in that machine?
- cpgxiii 6y ago
  The project is our internal monorepo, with probably order ~1000 targets, mostly C++, with reasonably heavy use of templates. GCC needs somewhere on the order of 2-4GB to compile each C++ target.
efreak 6y ago
> inodes Can't you deal with this by using a mounted filesystem?
- cpgxiii 6y ago
  Oh sure, it's fixable and something you can work around, but having your build system responsible for "machine is unresponsive and acts like it's out of disk but you've got >100GB space remaining" is a real pain in the ass. Running out of inodes (and specifically, that you can run out of them well before running out of disk space otherwise) is also really not an obvious failure mode to most people.

0xFFC 6y ago

Just curious, what specific project do you compile so that you ran out of resources in that machine?

cpgxiii 6y ago
The project is our internal monorepo, with probably order ~1000 targets, mostly C++, with reasonably heavy use of templates. GCC needs somewhere on the order of 2-4GB to compile each C++ target.

efreak 6y ago

> inodes Can't you deal with this by using a mounted filesystem?

cpgxiii 6y ago
Oh sure, it's fixable and something you can work around, but having your build system responsible for "machine is unresponsive and acts like it's out of disk but you've got >100GB space remaining" is a real pain in the ass. Running out of inodes (and specifically, that you can run out of them well before running out of disk space otherwise) is also really not an obvious failure mode to most people.