TypeScript: tsc compilation slow on moderate sized project

TypeScript Version: 3.9.0-dev.20200326

Search Terms:

tsc slow compilation, tsc memory, tsc slow Program time, tsc Program time

Code

I’m trying to debug why my typescript compiler is taking 9-13 seconds to recompile. This impacts ts-node and development drastically.

typescript version: ^3.X.X

tsconfig.json:

{
  "compilerOptions": {
    "extendedDiagnostics": true,
    "target": "es6",
    "lib": ["es2017"],
    "module": "commonjs",
    "emitDeclarationOnly": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "incremental": true,
    "noResolve": false,
    "noEmitOnError": false,
    "noImplicitAny": true,
    "declaration": true,
    "sourceMap": true,
    "outDir": "dist/",
    "moduleResolution": "node",
    "skipLibCheck": true
  },
  "include": [
    "src/**/*.ts",
    "test/**/*.ts"
  ],
  "exclude": [
    "node_modules"
  ]
}

npx tsc --listFiles --generateCpuProfile profile

Files: 732 Lines: 364288 Nodes: 1133413 Identifiers: 417612 Symbols: 236577 Types: 76 Instantiations: 0 Memory used: 330244K Assignability cache size: 0 Identity cache size: 0 Subtype cache size: 0 Strict subtype cache size: 0 I/O Read time: 2.51s Parse time: 3.77s ResolveTypeReference time: 0.33s ResolveModule time: 2.91s Program time: 9.86s Bind time: 1.39s Total time: 11.25s

File List Here: https://pastebin.com/zX7TpM2x

Generated CPU Profile Here: https://gist.github.com/rightisleft/d3c77fe2c643ba4c7832a94209f53ef2

Expected behavior:

This is a mid sized project, it should have a 1-3 second compile time

Actual behavior:

Compile takes anywhere from 9-14 seconds per line change

About this issue

Original URL
State: closed
Created 4 years ago
Comments: 16 (11 by maintainers)

Most upvoted comments

@mmahalwy I find that performance tracing is the most effective way to investigate excessive check time. Can you please give that a shot and file a new issue with the results (assuming you don’t figure it out yourself from the trace)?

amcasey on Nov 10, 2021

root@afdb413072d0:/app# ls -lag
total 5608
drwxr-xr-x  21 root     672 Mar 27 21:35 .
drwxr-xr-x   1 root    4096 Mar 27 21:38 ..
drwxr-xr-x  10 root     320 Mar 27 21:29 .idea
-rw-r--r--   1 root      90 Mar 26 20:12 .node-dev.json
-rw-r--r--   1 root       7 Mar 27 02:32 .npmignore
-rw-r--r--   1 root      70 Mar 12 13:44 .npmrc
-rw-r--r--   1 root    4962 Mar 12 13:44 README.md
drwxr-xr-x   5 root     160 Mar 27 02:32 config
drwxr-xr-x   5 root     160 Mar 27 02:39 dist
drwxr-xr-x 507 root   16224 Mar 27 21:35 node_modules
-rw-r--r--   1 root     449 Mar 27 02:32 nodemon.json
-rw-r--r--   1 root  231049 Mar 27 21:35 package-lock.json
-rw-r--r--   1 root    4134 Mar 27 21:29 package.json
-rw-r--r--   1 root      32 Mar 27 21:35 packagehash.txt
-rw-r--r--   1 root 2710358 Mar 27 02:58 profile
drwxr-xr-x   5 root     160 Mar 27 02:32 src
drwxr-xr-x   5 root     160 Mar 27 21:32 test
-rw-r--r--   1 root     568 Mar 28 18:39 tsconfig.json
-rw-r--r--   1 root    1386 Mar 12 13:44 tslint.json
root@afdb413072d0:/app# npx tsc --extendedDiagnostics
Files:                         781
Lines:                      442157
Nodes:                     1342298
Identifiers:                489887
Symbols:                    304554
Types:                       14191
Instantiations:              35092
Memory used:               404388K
Assignability cache size:     2695
Identity cache size:           278
Subtype cache size:            916
Strict subtype cache size:      99
I/O Read time:               1.81s
Parse time:                  3.33s
ResolveTypeReference time:   0.24s
ResolveModule time:          2.33s
Program time:                7.87s
Bind time:                   1.68s
Check time:                  1.61s
transformTime time:          0.13s
commentTime time:            0.02s
I/O Write time:              0.24s
printTime time:              0.49s
Emit time:                   0.49s
Total time:                 11.65s
root@afdb413072d0:/app# npx tsc --extendedDiagnostics
Files:                         781
Lines:                      442157
Nodes:                     1342298
Identifiers:                489887
Symbols:                    304554
Types:                       14191
Instantiations:              35092
Memory used:               405407K
Assignability cache size:     2695
Identity cache size:           278
Subtype cache size:            916
Strict subtype cache size:      99
I/O Read time:               1.94s
Parse time:                  3.20s
ResolveTypeReference time:   0.27s
ResolveModule time:          2.19s
Program time:                7.76s
Bind time:                   1.43s
Check time:                  1.38s
transformTime time:          0.13s
commentTime time:            0.02s
I/O Write time:              0.31s
printTime time:              0.56s
Emit time:                   0.56s
Total time:                 11.14s
root@afdb413072d0:/app# npx tsc --extendedDiagnostics
Files:                         781
Lines:                      442157
Nodes:                     1342298
Identifiers:                489887
Symbols:                    304554
Types:                       14191
Instantiations:              35092
Memory used:               405923K
Assignability cache size:     2695
Identity cache size:           278
Subtype cache size:            916
Strict subtype cache size:      99
I/O Read time:               1.42s
Parse time:                  3.22s
ResolveTypeReference time:   0.22s
ResolveModule time:          1.91s
Program time:                6.94s
Bind time:                   1.42s
Check time:                  1.40s
transformTime time:          0.14s
commentTime time:            0.03s
I/O Write time:              0.25s
printTime time:              0.50s
Emit time:                   0.50s
Total time:                 10.26s

rightisleft on Mar 28, 2020

Are the files in database/migrations enormous? The names make me think they might be generated.

amcasey on Mar 27, 2020

Now that I’ve looked at your file list, I’d guess there’s no reason to use project references, given that you appear to have only two test files (which, presumably, are not enormous?).

amcasey on Mar 27, 2020

@rightisleft Thanks for the detailed report!

Some initial observations, before I look at your CPU profile:

Your tsconfig has all the recommended settings for good perf.
It looks like your project is organized in such a way that you could trivially split it into separate composite projects for src and test - that would probably save you a bunch of time on every rebuild.
I’ve never seen extendedDiagnostics output with zero in those places. That actually looks like the output from --diagnostics, rather than --extendedDiagnostics (which would be a bug on us). Could you please try again with --extendedDiagnostics on the command line, rather than in the tsconfig?
I don’t think it’s even possible to have only 76 types.

amcasey on Mar 27, 2020