Size the worker's per-line render cache to hold a segment's DISTINCT lines (16384 -> 65536, overridable with IDATUI_LINE_CACHE). This was a recorded dead end — it does nothing for a cold sweep — but the rename fix created a second-sweep workload, and re-rendering after a rename is now 21% cheaper. lg_search 7123 -> 5628.

Result: {"status":"keep","total_ms":27552.6,"lg_boot_ms":759.2,"lg_decomp_ms":2754.1,"lg_graph_ms":1207.2,"lg_hex_ms":448,"lg_index_ms":69.6,"lg_listing_cold_ms":434.5,"lg_listing_warm_ms":442.9,"lg_nav_ms":6642.3,"lg_palette_ms":4.7,"lg_rename_ms":730.6,"lg_render_ms":223.6,"lg_search_ms":5627.5,"lg_split_ms":2268,"pure_graph_ms":218.7,"sm_boot_ms":465,"sm_decomp_ms":1290.8,"sm_graph_ms":720.7,"sm_hex_ms":436.1,"sm_index_ms":2.4,"sm_listing_cold_ms":267.2,"sm_listing_warm_ms":266.5,"sm_nav_ms":292.9,"sm_palette_ms":0.3,"sm_rename_ms":380.1,"sm_render_ms":255.5,"sm_search_ms":68.1,"sm_split_ms":1276.3,"fails":0}

1 files changed, 19 insertions, 1 deletions

diff --git a/server/patch_server.py b/server/patch_server.py
index b8f5453..f3cbe35 100644
--- a/server/patch_server.py
+++ b/server/patch_server.py
@@ -318,9 +318,27 @@ def _idatui_head_row(ea):
 
 
 import functools as _idatui_functools
+import os as _idatui_os
 
+#: Entries in the per-line render cache. Sized to hold a whole segment's
+#: DISTINCT lines rather than a working set, because the listing gets rendered
+#: TWICE: once when it is first walked, and again after a rename, which restates
+#: every row's text. bash's .text is 228 659 rows but only 53 363 distinct
+#: lines, and the difference between thrashing and not is the whole win:
+#:
+#:     maxsize   first sweep   second sweep   worker RSS
+#:      16 384     17.2 us/row   16.9 us/row      +29 MB
+#:      32 768     17.0           17.2            +52 MB
+#:      65 536     17.0           11.1            +75 MB
+#:     131 072     16.9           11.2            +75 MB   (working set fits)
+#:
+#: It is a bound, not a proportion: a bigger binary fills it and stops, so the
+#: cost is capped at ~56 MB whatever is open. Lower it with IDATUI_LINE_CACHE if
+#: a pool of workers is competing for memory.
+_IDATUI_LINE_CACHE = int(_idatui_os.environ.get("IDATUI_LINE_CACHE") or 65536)
 
-@_idatui_functools.lru_cache(maxsize=16384)
+
+@_idatui_functools.lru_cache(maxsize=_IDATUI_LINE_CACHE)
 def _idatui_line_parts(line):
     """``(text, spans, ops)`` for one tagged disassembly line -- memoised.