TUI: each prompt keystroke re-registers keymap layers (~15 ms JS per key) #60681

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1. isaacturnbull commented on Oct 30, 2026

   

   isaacturnbull

   on Oct 30, 2026

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   Fix: #60682
2. opencodejr commented on Oct 30, 2026

   

   opencodejrBot

   on Oct 30, 2026

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   Thanks for the detailed report and the PR. I could reproduce this.

   I ran the TUI on a PTY with an empty config, wrote 60 single characters 200 ms apart without submitting, and timed each write to the first output byte:

   build	p50 ms	p90 ms
   2.2.1 release	9.9 · 9.7 · 10.5	14.7 · 14.0 · 18.2
   latest dev (bf5d12c), from source	10.1 · 10.8	18.3 · 14.5
   dev + #60682	4.4 · 4.2	5.9 · 5.1

   The absolute numbers are lower than yours (probably a faster machine), but the gap is the same. That fits the prompt keymap layers re-registering on every keystroke, and it still happens on the latest dev. The script below is the PTY harness I used. The recording shows the typing session, though a delay this small doesn't really show up on screen.

   Related: #60682 (your fix) and #59294 (keeping keymap command objects stable).

   recording.mp4

   Reproduction script (latency.py)

   #!/usr/bin/env python3
   """Measure TUI keystroke latency: time from writing one printable char to the PTY
   until the TUI's first output byte. Usage: latency.py <cmd...>"""
   import os, pty, sys, time, select, struct, fcntl, termios, statistics, tempfile
   cmd = sys.argv[1:] or ["opencode"]
   home = tempfile.mkdtemp(prefix="oc-lat-")
   env = dict(os.environ, TERM="xterm-256color", HOME=home, XDG_CONFIG_HOME=home+"/.config",
              XDG_DATA_HOME=home+"/.data", XDG_STATE_HOME=home+"/.state", XDG_CACHE_HOME=home+"/.cache")
   pid, fd = pty.fork()
   if pid == 0:
       os.execvpe(cmd[0], cmd, env)
   fcntl.ioctl(fd, termios.TIOCSWINSZ, struct.pack("HHHH", 40, 120, 0, 0))
   def drain(t):
       end = time.monotonic() + t
       while time.monotonic() < end:
           r,_,_ = select.select([fd],[],[],0.05)
           if r:
               try: data = os.read(fd, 65536)
               except OSError: return
               # answer terminal queries minimally
               if b"\x1b[6n" in data: os.write(fd, b"\x1b[1;1R")
   drain(12)  # let the TUI boot
   lat = []
   for i in range(60):
       drain(0.2)
       t0 = time.monotonic()
       os.write(fd, b"abcdefghij"[i % 10:i % 10 + 1])
       r,_,_ = select.select([fd],[],[],2)
       if r:
           lat.append((time.monotonic()-t0)*1000); os.read(fd, 65536)
   os.kill(pid, 9)
   lat.sort()
   print(f"n={len(lat)} p50={statistics.median(lat):.1f}ms p90={lat[int(len(lat)*0.9)]:.1f}ms min={lat[0]:.1f}ms")

   Run it: python3 latency.py
3. opencodejr

   added

   reproduced

   on Oct 30, 2026
4. simonklee

   self-assigned this

   on Oct 31, 2026
5. simonklee commented on Oct 31, 2026

   

   simonklee

   on Oct 31, 2026

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   This will be fixed soon, thanks for reporting.
6. simonklee

   closed this as completedin #60913on Oct 31, 2026