diff --git a/.github/workflows/reusable-build-test-config.yml b/.github/workflows/reusable-build-test-config.yml
index bbbfb8e358..7fa7e84d53 100644
--- a/.github/workflows/reusable-build-test-config.yml
+++ b/.github/workflows/reusable-build-test-config.yml
@@ -312,6 +312,8 @@ jobs:
           [ "$COVERAGE_ENABLED" = "true" ] && BUILD_NPROC=$((BUILD_NPROC - 2))
           # Sanitizer builds are memory hungry; run the tests single-threaded
           [ "$SANITIZERS_ON" = "true" ] && BUILD_NPROC=1
+          # Never drop below one job (small runners could go to 0 or negative above)
+          [ "$BUILD_NPROC" -ge 1 ] || BUILD_NPROC=1
 
           # The resolver/preload workaround is only correct for the ASan build:
           # a regular build doesn't hit the __dn_expand interceptor bug, and must
diff --git a/docs/build/sanitizers.md b/docs/build/sanitizers.md
index 6e7284fd06..92778fffc0 100644
--- a/docs/build/sanitizers.md
+++ b/docs/build/sanitizers.md
@@ -97,6 +97,11 @@ export TSAN_OPTIONS="include=sanitizers/suppressions/runtime-tsan-options.txt:su
 ./xrpld --unittest --unittest-jobs=5
 ```
 
+`runtime-tsan-options.txt` sets `halt_on_error=true`, so the process aborts on
+the first unsuppressed report. To collect all reports in one run instead (e.g.
+when triaging locally), append `:halt_on_error=false` to `TSAN_OPTIONS`; the
+exit code is still non-zero (66) if any report was produced.
+
 More details [here](https://github.com/google/sanitizers/wiki/ThreadSanitizerCppManual).
 
 ### LeakSanitizer (LSan)
diff --git a/sanitizers/suppressions/runtime-tsan-options.txt b/sanitizers/suppressions/runtime-tsan-options.txt
index aafe997ea4..aee06c7d80 100644
--- a/sanitizers/suppressions/runtime-tsan-options.txt
+++ b/sanitizers/suppressions/runtime-tsan-options.txt
@@ -1,3 +1,3 @@
-halt_on_error=false
+halt_on_error=true
 verbosity=1
 second_deadlock_stack=1
diff --git a/sanitizers/suppressions/tsan.supp b/sanitizers/suppressions/tsan.supp
index df2e200349..47e94dc214 100644
--- a/sanitizers/suppressions/tsan.supp
+++ b/sanitizers/suppressions/tsan.supp
@@ -3,24 +3,22 @@
 # Races in rippled's own code should be fixed, not suppressed.
 
 # Boost ASIO / Boost Context false positives
-# These are internal to Boost's reactor, fiber context switching, and memory management.
+# These are internal to Boost's reactor and the fiber context switching used
+# by boost::asio::spawn (server Spawn.h, test yield_to.h).
+# NOTE: a suppression fires if ANY frame in the report matches, so these
+# path patterns can also hide rippled races that merely pass through asio
+# (e.g. handlers running on an io_context). Narrow them to specific frames
+# once TSAN runs cleanly.
 race:boost/asio/
 race:boost/context/
-race:boost/asio/executor.hpp
-race:boost::asio
-race:boost::context::fiber::resume
-race:boost::asio::detail::spawned_fiber_thread
-race:boost::asio::detail::spawned_fiber_thread::suspend_with
-race:boost::asio::detail::spawned_fiber_thread::destroy
 race:__cxxabiv1::manage_exception_state
-race:__tsan_memcpy
 
 # TSAN's own syscall interceptors and libc internals
 # These are false positives from TSAN's fd tracking in glibc.
 # TODO: Tighten these suppressions once TSAN runs cleanly — they may mask
 # real fd-lifetime bugs in rippled's networking code.
 race:crtstuff.c
-race:pipe
+race:__pipe
 race:epoll_ctl
 race:epoll_create
 race:closedir
@@ -33,7 +31,6 @@ race:eventfd
 # C++ standard library internals
 race:ostreambuf_iterator
 race:basic_ostream
-called_from_lib:libclang_rt
 
 # Deadlock false positives in Boost and threading primitives
 deadlock:pthread_create
@@ -71,9 +68,7 @@ deadlock:xrpl::doLedgerAccept
 deadlock:beast::PropertyStream::Source
 
 # Signal/crash suppressions for GCC TSAN instrumentation issues
-signal:std::__cxx11::basic_stringbuf
 signal:basic_stringbuf
 signal:basic_ostringstream
 signal:boost::asio::aligned_new
 signal:boost::asio::detail::memory
-signal:execute_native_thread_routine