EMFILE: too many open files, watch cypress.json

Description

I know there is an advise for this the problem, but I cannot fix it. The open command should just work and it seems to be a node_module cypress uses. Please, have a look.

Error

Error: EMFILE: too many open files, watch

Facts

I have set redicolously high values for ulimits

❯ ulimit -n
500000
❯ sudo sysctl -a | grep fs.file-max
fs.file-max = 9223372036854775807
❯ cat /proc/sys/fs/inotify/max_user_watches
524288

Looks like this fs.watch ist not async:

102 function createFsWatchInstance(path, options, listener, errHandler, emitRaw) {
103   const handleEvent = (rawEvent, evPath) => {
104     listener(path);
105     emitRaw(rawEvent, evPath, {watchedPath: path});
106 
107     // emit based on events occurring for files from a directory's watcher in
108     // case the file's watcher misses it (and rely on throttling to de-dupe)
109     if (evPath && path !== evPath) {
110       fsWatchBroadcast(
111         sysPath.resolve(path, evPath), KEY_LISTENERS, sysPath.join(path, evPath)
112       );
113     }
114   };
115   try {
116     return fs.watch(path, options, handleEvent);
117   } catch (error) {
118     errHandler(error);
119   }
120 }

Current behavior

npx cypress open

❯ npx cypress open
[313284:0608/135242.546859:ERROR:proxy_config_service_linux.cc(607)] inotify_init failed: Zu viele offene Dateien (24)
[313284:0608/135242.547107:ERROR:file_path_watcher_linux.cc(315)] inotify_init() failed: Zu viele offene Dateien (24)
libva error: vaGetDriverNameByIndex() failed with unknown libva error, driver_name = (null)
[313284:0608/135243.947389:ERROR:proxy_config_service_linux.cc(607)] inotify_init failed: Zu viele offene Dateien (24)
Error: EMFILE: too many open files, watch '/datadisk/projects/cypress/first_test/cypress.json'
    at FSWatcher.<computed> (internal/fs/watchers.js:218:26)
    at Object.watch (fs.js:1525:34)
    at createFsWatchInstance (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:116:15)
    at setFsWatchListener (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:163:15)
    at NodeFsHandler._watchWithNodeFs (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:325:14)
    at NodeFsHandler._handleFile (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:355:23)
    at NodeFsHandler._addToNodeFs (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:617:21)
    at /home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/index.js:435:21
    at Function.all (<anonymous>:null:null)
 {
  errno: -24,
  syscall: 'watch',
  code: 'EMFILE',
  path: '/datadisk/projects/cypress/first_test/cypress.json',
  filename: '/datadisk/projects/cypress/first_test/cypress.json'
}
Error: EMFILE: too many open files, watch '/datadisk/projects/cypress/first_test/cypress.json'
    at FSWatcher.<computed> (internal/fs/watchers.js:218:26)
    at Object.watch (fs.js:1525:34)
    at createFsWatchInstance (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:116:15)
    at setFsWatchListener (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:163:15)
    at NodeFsHandler._watchWithNodeFs (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:325:14)
    at NodeFsHandler._handleFile (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:355:23)
    at NodeFsHandler._addToNodeFs (/home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/lib/nodefs-handler.js:617:21)
    at /home/markus/.cache/Cypress/7.5.0/Cypress/resources/app/packages/server/node_modules/chokidar/index.js:435:21
    at Function.all (<anonymous>:null:null)

Desired behavior

Just run cypress as described in docu.

Test code to reproduce

Follow docu to install cypress

• npm install
• npx cypress open

Versions

❯ node --version
v16.3.0
❯ npm --version
7.15.1
* Cypress/7.5.0

OS

Linux  5.8.0-55-generic #62~20.04.1-Ubuntu SMP Wed Jun 2 08:55:04 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

[marmelin]

[SOLVED] ✔️ Fixed with fs.inotify.max_user_instances = 256

For Linux:

Check current value of max_user_instances: $ cat /proc/sys/fs/inotify/max_user_instances increase that value: $ echo 256 > /proc/sys/fs/inotify/max_user_instances

Note: sudo … does not work, you have to switch to root or use sudo su -c ...

In order to make that change permanent add a line to /etc/sysctl.conf: fs.inotify.max_user_instances = 256

[jennifer-shehane]

@marmelin Thanks for sharing your solution.