Question related to FallbackProvider

[IronSight87]

Hi there,

I want to send one transaction to multiple nodes at the same time to have a higher chance to get my transaction mined fast. My understanding is that FallbackProvider is just right for the job. Please see my code below. Is this the right way or is there a better way to archive what I want to do?

let provider1=new ethers.providers.WebSocketProvider(url[0])
let provider2=new ethers.providers.WebSocketProvider(url[1])
let provider3=new ethers.providers.WebSocketProvider(url[2])

let fallbackProvider=new ethers.providers.FallbackProvider([
{provider: provider1, priority: 1, weight: 1, stallTimeout: 0}
{provider: provider2, priority: 1, weight: 1, stallTimeout: 0}
{provider: provider2, priority: 1, weight: 1, stallTimeout: 0}
] , 1)

[ricmoo]

You could also just pass the three providers into the FallbackProvider and it will create the config for you; the stallTimeout is ignored for sendTransaction. :)

[IronSight87]

Cheers @ricmoo

[IronSight87]

Hi @ricmoo,

sorry to bother you again, but when I call a method like getBalance() the response will not return until all nodes responded, even if the stallTimeout is set to 0. Is this the desired behavior?

[IronSight87]

I checked each node detached from the others multiple times and only one is responding late (after about 10 seconds). The another two are responding almost instantly

[IronSight87]

@ricmoo Any idea about that?

[IronSight87]

@ricmoo What I’m doing wrong?

[ricmoo]

I’m not sure, but don’t have the time to look into that right now. If you have some time, you can add console.logs to see what is going on? Otherwise, give me time to look into it.

[IronSight87]

@ricmoo I did a little bit of debugging and it seems that the detectNetwork() method of the FallbackProvider is the issue.
This line seems to be the bad guy as it will not return until all nodes responding
const networks = await Promise.all(this.providerConfigs.map((c) => c.provider.getNetwork()));

What I did to produce the problem:

1. Initialize FallbackProvider like mentioned in my first comment
2. Used pfctl on macOS to throttle the traffic for one specific node to make it respond slower
3. Debugging ;)