chipsenkbeil/distant

Server hangs

chipsenkbeil opened this issue · 2 comments

I'd seen this as part of #175, so this may be related.

Recent changes to support batch processing seem to trigger this more frequently on writing. In particular, using distant.nvim to write works fine, but once I leave neovim and rejoin, the server appears to hang. So there may be a busy loop somewhere.

Points to investigate

Using tokio-console, I can see some resources are growing and never disappearing, which may be a sign of issues.

Manager without doing anything:

  • distant/distant-net/src/server.rs:183 (tokio::sync::rwlock)
  • distant/distant-net/src/server/ref.rs:57 (tokio::time::sleep) - bunch of these being created, about 10 per second with no connections (seems to be polling_wait)

After connecting a client to the manager:

  • distant/distant-net/src/client.rs:269 (tokio::time::sleep) - bunch of these being created
  • distant/distant-net/src/client.rs:397 (tokio::time::sleep) - bunch of these being created

Connection task never wakes up again:

  • distant/distant-net/src/server/connect:?? (tokio::task) - seems to occasionally come back to running even with the idle and waker warning (too long to see line, possibly the tokio::spawn for handler.on_request on line 500

Screenshots

TASKS

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RESOURCES

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HTOP

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For this one, high CPU could be due to tracing.

Example of sleep task that has lost association:

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Compared to one with an association:

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Also notice the large ms time

Manager server rwlock

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Keychain writing

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Two separate task sources for RwLock::write. Could that be a problem?

Once hangup happens

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Flood of client and server connection sleep events. Wondering if there's an issue with reconnecting or something.

The only sleep in the connection file is waiting for a read or write availability where read and write are blocked. This is done in a loop, so we could add logging here to report when being fully blocked starts and ends.

  • distant/distant-net/src/client:269 - client is checking ready status (sleep used as timeout condition)
  • distant/distant-net/src/client:397 - client is waiting for read or write
  • distant/distant-net/src/server/connection:585 - server is waiting for read or write

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues. If you have found a problem that seems similar to this, please open a new issue and complete the issue template so we can capture all the details necessary to investigate further.