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Too many listeners

See original GitHub issue

When sending a transaction, I get an error:

(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit.

It’s coming from the Filter subprovider onFilterChange _ready.on method. That _ready object needs its listener max raised, or has a memory leak.

Issue Analytics

State:
Created 7 years ago
Reactions:5
Comments:17 (5 by maintainers)

Top GitHub Comments

1reaction

riteablecommented, Sep 27, 2017

I don’t seem to have this issue in the browser, but I do get the warning in Node.js.

MaxListenersExceededWarning: Possible EventEmitter memory leak detected. 11 unlock listeners added. Use emitter.setMaxListeners() to increase limit
    at _addListener (events.js:262:19)
    at Stoplight.addListener (events.js:279:10)
    at Stoplight.once (events.js:308:8)
    at Stoplight.await (/.../node_modules/web3-provider-engine/util/stoplight.js:30:10)
    at FilterSubprovider.handleRequest (/.../node_modules/web3-provider-engine/subproviders/filters.js:69:24)
    at next (/.../node_modules/web3-provider-engine/index.js:112:18)
    at Web3ProviderEngine._handleAsync (/.../node_modules/web3-provider-engine/index.js:99:3)
    at /.../node_modules/async/internal/map.js:27:9
    at eachOfArrayLike (/.../node_modules/async/eachOf.js:65:9)
    at exports.default (/.../node_modules/async/eachOf.js:9:5)
    at _asyncMap (/.../node_modules/async/internal/map.js:25:5)

I’m using 0x on the server side and using the web3 provider engine to listen to certain 0x log events (fill, cancel, error). I’ve added the filter and RPC subproviders. The RPC subprovider is connected to Infura.

1reaction

ghostcommented, Apr 25, 2017

Adding this line to the top of server.js makes the error not show up again: require('events').EventEmitter.prototype._maxListeners = 100;