Refresh guest deadline after MySQL hostcalls

docs/wasm-runtime-architecture.md

@@ -407,6 +407,10 @@ header free-functions are `inline`. The wasm backend exposes only declarations
   caller props are restored. Its warm-request ceiling guards the request-scope
   invariant that entering a nested component swaps the active prop trees in
   constant time instead of deep-copying the outer tree for every child.
+  `scripts/test_mysql_epoch_refresh.sh` spends more than half of the configured
+  guest epoch on each side of a real MySQL query. It proves the blocking
+  database hostcall refreshes the guest deadline so cumulative request work is
+  allowed while a CPU loop without intervening host work still traps.
 
 - **Log timeliness**: the base process line-buffers stdout before forking
   workers, the proactive compiler, and the WebSocket broker. This keeps each

scripts/run_cli_tests.sh

@@ -70,5 +70,6 @@ if [[ "$action" == "run" ]]; then
 	scripts/test_cold_component_deadline.sh
 	scripts/test_nested_component_props.sh
 	scripts/test_password_hashing.sh
+	scripts/test_mysql_epoch_refresh.sh
 	scripts/test_log_timeliness.sh
 fi

scripts/test_mysql_epoch_refresh.sh

@@ -0,0 +1,70 @@
+#!/usr/bin/env bash
+set -euo pipefail
+cd "$(dirname "$0")/.."
+
+test_name="mysql-epoch-refresh-test-$$"
+site_directory="${UCE_TEST_SITE_DIRECTORY:-site}"
+settings_file="${UCE_SETTINGS_FILE:-/etc/uce/settings.cfg}"
+if [[ -z "${UCE_TEST_SITE_DIRECTORY:-}" && -r "$settings_file" ]]; then
+	configured_site_directory=$(awk -F= '/^[[:space:]]*SITE_DIRECTORY[[:space:]]*=/ {gsub(/^[[:space:]]+|[[:space:]]+$/, "", $2); print $2; exit}' "$settings_file")
+	if [[ -n "${configured_site_directory:-}" ]]; then
+		site_directory="$configured_site_directory"
+	fi
+fi
+source_dir="$site_directory/$test_name"
+bin_directory="${BIN_DIRECTORY:-}"
+if [[ -z "$bin_directory" && -r "$settings_file" ]]; then
+	bin_directory=$(awk -F= '/^[[:space:]]*BIN_DIRECTORY[[:space:]]*=/ {gsub(/^[[:space:]]+|[[:space:]]+$/, "", $2); print $2; exit}' "$settings_file")
+fi
+bin_directory="${bin_directory:-/tmp/uce/work}"
+ticks=$(awk -F= '/^[[:space:]]*WASM_EPOCH_DEADLINE_TICKS[[:space:]]*=/ {gsub(/^[[:space:]]+|[[:space:]]+$/, "", $2); print $2; exit}' "$settings_file" 2>/dev/null || true)
+period_ms=$(awk -F= '/^[[:space:]]*WASM_EPOCH_PERIOD_MS[[:space:]]*=/ {gsub(/^[[:space:]]+|[[:space:]]+$/, "", $2); print $2; exit}' "$settings_file" 2>/dev/null || true)
+ticks="${ticks:-200}"
+period_ms="${period_ms:-50}"
+segment_seconds=$(awk -v ticks="$ticks" -v period="$period_ms" 'BEGIN { printf "%.6f", ticks * period * 0.00055 }')
+cache_dir=""
+test_user="uce_epoch_$$"
+test_password=$(printf '%s' "$test_name-$(date +%s%N)" | sha256sum | cut -c1-32)
+test_user_created=false
+
+cleanup() {
+	if [[ "$test_user_created" == true ]]; then
+		mariadb -e "DROP USER IF EXISTS '$test_user'@'127.0.0.1'" >/dev/null 2>&1 || true
+	fi
+	rm -rf "$source_dir"
+	if [[ -n "$cache_dir" ]]; then
+		rm -rf "$cache_dir"
+	fi
+}
+trap cleanup EXIT
+mkdir -p "$source_dir"
+cache_dir="$bin_directory$(realpath "$source_dir")"
+mariadb -e "DROP USER IF EXISTS '$test_user'@'127.0.0.1'; CREATE USER '$test_user'@'127.0.0.1' IDENTIFIED BY '$test_password'"
+test_user_created=true
+
+printf '%s\n' \
+	'void mysql_epoch_burn(f64 seconds) {' \
+	'  f64 deadline = time_precise() + seconds;' \
+	'  u64 spins = 0; while(time_precise() < deadline) spins++;' \
+	'}' \
+	'CLI(Request& context) {' \
+	"  MySQL* db = mysql_connect(\"127.0.0.1\", \"$test_user\", \"$test_password\");" \
+	'  if(db == 0 || mysql_error(db) != "") { print("mysql-connect-failed:", db == 0 ? "null" : mysql_error(db)); return; }' \
+	"  mysql_epoch_burn($segment_seconds);" \
+	'  mysql_query(db, "SELECT 1 AS value");' \
+	"  mysql_epoch_burn($segment_seconds);" \
+	'  mysql_query(db, "SELECT 2 AS value");' \
+	'  if(mysql_error(db) == "") print("mysql-epoch-refresh-ok"); else print("mysql-query-failed:", mysql_error(db));' \
+	'  mysql_disconnect(db);' \
+	'}' >"$source_dir/test.uce"
+
+output=$(scripts/uce-cli "/$test_name/test.uce" 2>&1) || {
+	echo "MySQL hostcall did not refresh the guest epoch deadline: $output" >&2
+	exit 1
+}
+if [[ "$output" != "mysql-epoch-refresh-ok" ]]; then
+	echo "MySQL epoch refresh failed: $output" >&2
+	exit 1
+fi
+
+echo "MySQL epoch refresh passed with ${segment_seconds}s guest segments"

src/wasm/worker.cpp

@@ -2416,7 +2416,7 @@ private:
 				return(std::monostate());
 			}));
 		if(mod == "env" && name == "uce_host_mysql")
-			return(add([self](Caller, Span<const Val> args, Span<Val> results) -> Result<std::monostate, Trap> {
+			return(add([self](Caller caller, Span<const Val> args, Span<Val> results) -> Result<std::monostate, Trap> {
 				String encoded;
 				self->hostcall_read(args[0].i32(), args[1].i32(), encoded);
 				u32 cap = (u32)args[3].i32();
@@ -2499,6 +2499,7 @@ private:
 				}
 				if(buf != 0 && cap >= out.size())
 					self->hostcall_write(buf, out);
+				caller.context().set_epoch_deadline(self->worker.cfg.epoch_deadline_ticks);
 				results[0] = Val((int32_t)out.size());
 				return(std::monostate());
 			}));