PuTTY bug spew-lockup

summary: Remote terminal spew can freeze terminal and lock out local GUI
class: bug: This is clearly an actual problem we want fixed.
priority: high: This should be fixed in the next release.
absent-in: 0.57
present-in: 2004-12-23 0.58
fixed-in: 2007-01-08 r7071 (0.59) (0.60) (0.61) (0.62)

If the remote server floods us with terminal data enthusiastically enough, it can saturate us with input data, completely locking out the local GUI (at least on Windows). The appearance is that PuTTY appears to hang: it consumes as much CPU as it can, the terminal display does not update, and the GUI (keyboard, menus etc) is unresponsive. If and when the stream of data abates, PuTTY becomes responsive again.

This crept in somewhere between 0.57 and 0.58.

I (JTN) seem to recall noticing that some code which periodically gave the GUI a chance to update disappeared in some upheaval or other, but I didn't follow it up at the time and haven't got round to digging it up again.

SGT, 2007-01-07: I think this came in at r4906, when I removed the pending_netevent mechanism in the process of setting up the new timing infrastructure. Putting it back in seems to solve it.

Audit trail for this bug.

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(last revision of this bug record was at 2007-01-07 12:40:21 +0000)