Pnpm: Babel run time spikes significantly when project is installed with pnpm

[andreypopp]

pnpm version: 0.48.0

Code to reproduce the issue:

% git clone https://github.com/prometheusresearch/react-ui.git
% cd react-ui
% pnpm install
% make build # observe it takes sooo long

Expected behavior:

Babel run time shouldn't be so big.

Additional information:

• node -v prints: v6.9.1
• OS X

[andreypopp]

Looks like the issue manifests itself only with --preserve-symlinks activated. Do we require it for recent Node versions? Looks like it works without it also.

That's how flamechart looks for compiling a single file with Babel, Node's algo with the presence of --preserve-symlinks looks suboptimal:

[zkochan]

You were faster, I wanted to suggest this:

Could you please also check how it works without preserve-symlinks?

• run npm config set preserve-symlinks false
• remove node_modules and reinstall (the store shouldn't be removed, from [email protected] the store is immutable

[andreypopp]

Yes, much faster that way. What's the story with --preserve-symlinks? Is it required for pnpm to work correctly? Is it going to be deprecated by Node?

Hm... I still see Jest's runtime suffer (make test).

[zkochan]

Seems like it is going to be deprecated by Node... But pnpm works fine without --preserve-symlinks since 0.47.0. I was actually waiting for a reason to remove preserve-symlinks, so here it is :smile:

[zkochan]

We can make preserve-symlinks false by default once #571 gets merged.