Use a local allocator for tile data

Author: hummeltech

src/mod_tile.c

@@ -1556,7 +1556,35 @@ static int tile_handler_serve(request_rec *r)
 	gettimeofday(&start, NULL);
 
 	// FIXME: It is a waste to do the malloc + read if we are fulfilling a HEAD or returning a 304.
+#ifdef __MACH__
+/*
+ * macOS Compatibility: Create a dedicated allocator and independent pool for the tile buffer.
+ * The allocator's max_free is limited to prevent memory fragmentation during high traffic.
+ */
+	apr_pool_t *tp;
+	apr_allocator_t *pa;
+
+	if (apr_allocator_create(&pa) != APR_SUCCESS) {
+		ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,
+			      "Failed to create tile buffer allocator");
+		return HTTP_INTERNAL_SERVER_ERROR;
+	}
+
+	apr_allocator_max_free_set(pa, 1);
+
+	if (apr_pool_create_ex(&tp, NULL, NULL, pa) != APR_SUCCESS) {
+		ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,
+			      "Failed to create tile buffer pool");
+		apr_allocator_destroy(pa);
+		return HTTP_INTERNAL_SERVER_ERROR;
+	}
+
+	apr_allocator_owner_set(pa, tp);
+
+	buf = (char *)apr_palloc(tp, tile_max);
+#else
 	buf = (char *)apr_pcalloc(r->pool, tile_max);
+#endif
 
 	if (!buf) {
 		if (!incRespCounter(HTTP_INTERNAL_SERVER_ERROR, r, cmd, rdata->layerNumber)) {
@@ -1607,6 +1635,10 @@ static int tile_handler_serve(request_rec *r)
 		incTimingCounter((end.tv_sec * 1000000 + end.tv_usec) - (start.tv_sec * 1000000 + start.tv_usec), cmd->z, r);
 
 		if ((errstatus = ap_meets_conditions(r)) != OK) {
+#ifdef __MACH__
+			apr_pool_destroy(tp);
+#endif
+
 			if (!incRespCounter(errstatus, r, cmd, rdata->layerNumber)) {
 				ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,
 					      "Failed to increase response stats counter");
@@ -1615,6 +1647,9 @@ static int tile_handler_serve(request_rec *r)
 			return errstatus;
 		} else {
 			ap_rwrite(buf, len, r);
+#ifdef __MACH__
+			apr_pool_destroy(tp);
+#endif
 
 			if (!incRespCounter(errstatus, r, cmd, rdata->layerNumber)) {
 				ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r,
@@ -1625,6 +1660,9 @@ static int tile_handler_serve(request_rec *r)
 		}
 	}
 
+#ifdef __MACH__
+	apr_pool_destroy(tp);
+#endif
 	ap_log_rerror(APLOG_MARK, APLOG_WARNING, 0, r, "Failed to read tile from disk: %s", err_msg);
 
 	if (!incRespCounter(HTTP_NOT_FOUND, r, cmd, rdata->layerNumber)) {