PowerShell / PowerShell/Win32-OpenSSH

"Too many open files" error when using ssh tunnel for SOCKS proxy

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Description

Prerequisites
  • Write a descriptive title.
  • Make sure you are able to repro it on the latest version
  • Search the existing issues.
Steps to reproduce

I use an ssh connection to proxy some calls through a remote. Just with one or two browser pages (apnews.com for example) I start getting accept: Too many open files messages in the ssh console. Typically this would indicate a remote system limit and I spent a lot of time chasing that. Not so in this case. While the issue is happening, the remote system reports FD's in use far less than the set limits.
At first I used Windows's built-in ssh client and it had this problem.
Then I tried the one that comes with Git for Windows and under similar loads I was not able to make the issue show up again.
Then I got the latest available release (v.10) from this project and the problem is back. Hence this bug report.

Expected behavior
I'd expect the ssh client to handle such relatively light use without a problem by default. And provide configuration for heavier use.
Actual behavior
The ssh client is experiencing problems under what I'd consider to be a light load.
Error details

Environment data
Name                           Value
----                           -----
PSVersion                      7.5.4
PSEdition                      Core
GitCommitId                    7.5.4
OS                             Microsoft Windows 10.0.26200
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0
Version

10.0.0.0

Visuals

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Contributor guide

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First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the SOCKS-proxy workload described with OpenSSH v10 on Windows 10, using one or two browser pages and observing the ssh console for “accept: Too many open files.” Compare the behavior with Windows’ built-in client and Git for Windows; done requires identifying the cause and preventing the error under the reported light load.

Written by the indexing model from the issue text.

Assessment

Domain
networking
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
35/100

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