[PATCH] D39843: [clangd] Use in-memory preambles in clangd.

[Ilya Biryukov via Phabricator via cfe-commits]

ilya-biryukov added a comment.

After looking at the numbers, I think we should make this configurable. I'll update this change accordingly. Not sure what should be the default, though. I'm currently erring on the side of "in-memory by default".

Current implementation eats almost twice as much memory, which quickly adds up (tried comparing with earlier builds on `ClangdUnit.cpp`).
Even without proper benchmarks, it's clear that if we run out of memory (and we easily could if run on a machine with, say, 8GB of RAM) on-disk preambles are an easy way out of trouble.


https://reviews.llvm.org/D39843