Use single memory pool for result metadata and result set.

10 files changed, 121 insertions, 81 deletions

diff --git a/ext/mysqlnd/mysqlnd_block_alloc.c b/ext/mysqlnd/mysqlnd_block_alloc.c
index db183a4fb3..80aa3ffe14 100644
--- a/ext/mysqlnd/mysqlnd_block_alloc.c
+++ b/ext/mysqlnd/mysqlnd_block_alloc.c
@@ -76,6 +76,25 @@ static zend_always_inline void* mysqlnd_arena_alloc(zend_arena **arena_ptr, size
 }
 /* }}} */
 
+static zend_always_inline void* mysqlnd_arena_checkpoint(zend_arena *arena)
+{
+	return arena->ptr;
+}
+
+static zend_always_inline void mysqlnd_arena_release(zend_arena **arena_ptr, void *checkpoint)
+{
+	zend_arena *arena = *arena_ptr;
+
+	while (UNEXPECTED((char*)checkpoint > arena->end) ||
+	       UNEXPECTED((char*)checkpoint <= (char*)arena)) {
+		zend_arena *prev = arena->prev;
+		mnd_efree(arena);
+		*arena_ptr = arena = prev;
+	}
+	ZEND_ASSERT((char*)checkpoint > (char*)arena && (char*)checkpoint <= arena->end);
+	arena->ptr = (char*)checkpoint;
+}
+
 /* {{{ mysqlnd_mempool_free_chunk */
 static void
 mysqlnd_mempool_free_chunk(MYSQLND_MEMORY_POOL * pool, void * ptr)
@@ -145,6 +164,8 @@ mysqlnd_mempool_create(size_t arena_size)
 	arena = mysqlnd_arena_create(MAX(arena_size, sizeof(zend_arena)));
 	ret = mysqlnd_arena_alloc(&arena, sizeof(MYSQLND_MEMORY_POOL));
 	ret->arena = arena;
+	ret->last = NULL;
+	ret->checkpoint = NULL;
 	ret->get_chunk = mysqlnd_mempool_get_chunk;
 	ret->free_chunk = mysqlnd_mempool_free_chunk;
 	ret->resize_chunk = mysqlnd_mempool_resize_chunk;
@@ -164,6 +185,29 @@ mysqlnd_mempool_destroy(MYSQLND_MEMORY_POOL * pool)
 }
 /* }}} */
 
+/* {{{ mysqlnd_mempool_save_state */
+PHPAPI void
+mysqlnd_mempool_save_state(MYSQLND_MEMORY_POOL * pool)
+{
+	DBG_ENTER("mysqlnd_mempool_save_state");
+	pool->checkpoint = mysqlnd_arena_checkpoint(pool->arena);
+	DBG_VOID_RETURN;
+}
+/* }}} */
+
+/* {{{ mysqlnd_mempool_restore_state */
+PHPAPI void
+mysqlnd_mempool_restore_state(MYSQLND_MEMORY_POOL * pool)
+{
+	DBG_ENTER("mysqlnd_mempool_restore_state");
+	if (pool->checkpoint) {
+		mysqlnd_arena_release(&pool->arena, pool->checkpoint);
+		pool->last = NULL;
+		pool->checkpoint = NULL;
+	}
+	DBG_VOID_RETURN;
+}
+/* }}} */
 
 /*
  * Local variables:
diff --git a/ext/mysqlnd/mysqlnd_block_alloc.h b/ext/mysqlnd/mysqlnd_block_alloc.h
index 8a2e2a6746..f95ed6e006 100644
--- a/ext/mysqlnd/mysqlnd_block_alloc.h
+++ b/ext/mysqlnd/mysqlnd_block_alloc.h
@@ -22,6 +22,8 @@
 
 PHPAPI MYSQLND_MEMORY_POOL *	mysqlnd_mempool_create(size_t arena_size);
 PHPAPI void 					mysqlnd_mempool_destroy(MYSQLND_MEMORY_POOL * pool);
+PHPAPI void						mysqlnd_mempool_save_state(MYSQLND_MEMORY_POOL * pool);
+PHPAPI void						mysqlnd_mempool_restore_state(MYSQLND_MEMORY_POOL * pool);
 
 #endif	/* MYSQLND_BLOCK_ALLOC_H */
 
diff --git a/ext/mysqlnd/mysqlnd_ps.c b/ext/mysqlnd/mysqlnd_ps.c
index 9e8687fc4f..f1dac944ae 100644
--- a/ext/mysqlnd/mysqlnd_ps.c
+++ b/ext/mysqlnd/mysqlnd_ps.c
@@ -82,7 +82,7 @@ MYSQLND_METHOD(mysqlnd_stmt, store_result)(MYSQLND_STMT * const s)
 	result->type			= MYSQLND_RES_PS_BUF;
 /*	result->m.row_decoder = php_mysqlnd_rowp_read_binary_protocol; */
 
-	result->stored_data	= (MYSQLND_RES_BUFFERED *) mysqlnd_result_buffered_zval_init(result->field_count, TRUE);
+	result->stored_data	= (MYSQLND_RES_BUFFERED *) mysqlnd_result_buffered_zval_init(result, result->field_count, TRUE);
 	if (!result->stored_data) {
 		SET_OOM_ERROR(conn->error_info);
 		DBG_RETURN(NULL);
@@ -122,7 +122,7 @@ MYSQLND_METHOD(mysqlnd_stmt, store_result)(MYSQLND_STMT * const s)
 	} else {
 		COPY_CLIENT_ERROR(conn->error_info, result->stored_data->error_info);
 		stmt->result->m.free_result_contents(stmt->result);
-		mnd_efree(stmt->result);
+		mysqlnd_mempool_destroy(stmt->result->memory_pool);
 		stmt->result = NULL;
 		stmt->state = MYSQLND_STMT_PREPARED;
 	}
@@ -173,7 +173,7 @@ MYSQLND_METHOD(mysqlnd_stmt, get_result)(MYSQLND_STMT * const s)
 			break;
 		}
 
-		result->meta = stmt->result->meta->m->clone_metadata(stmt->result->meta);
+		result->meta = stmt->result->meta->m->clone_metadata(result, stmt->result->meta);
 		if (!result->meta) {
 			SET_OOM_ERROR(conn->error_info);
 			break;
@@ -251,14 +251,21 @@ mysqlnd_stmt_skip_metadata(MYSQLND_STMT * s)
 	unsigned int i = 0;
 	enum_func_status ret = FAIL;
 	MYSQLND_PACKET_RES_FIELD field_packet;
+	MYSQLND_MEMORY_POOL * pool;
 
 	DBG_ENTER("mysqlnd_stmt_skip_metadata");
 	if (!stmt || !conn) {
 		DBG_RETURN(FAIL);
 	}
+	pool = mysqlnd_mempool_create(MYSQLND_G(mempool_default_size));
+	if (!pool) {
+		DBG_RETURN(FAIL);
+	}
 	DBG_INF_FMT("stmt=%lu", stmt->stmt_id);
 
 	conn->payload_decoder_factory->m.init_result_field_packet(&field_packet);
+	field_packet.memory_pool = pool;
+
 	ret = PASS;
 	field_packet.skip_parsing = TRUE;
 	for (;i < stmt->param_count; i++) {
@@ -268,6 +275,7 @@ mysqlnd_stmt_skip_metadata(MYSQLND_STMT * s)
 		}
 	}
 	PACKET_FREE(&field_packet);
+	mysqlnd_mempool_destroy(pool);
 
 	DBG_RETURN(ret);
 }
@@ -1835,12 +1843,12 @@ MYSQLND_METHOD(mysqlnd_stmt, result_metadata)(MYSQLND_STMT * const s)
 			break;
 		}
 		result_meta->type = MYSQLND_RES_NORMAL;
-		result_meta->unbuf = mysqlnd_result_unbuffered_init(stmt->field_count, TRUE);
+		result_meta->unbuf = mysqlnd_result_unbuffered_init(result_meta, stmt->field_count, TRUE);
 		if (!result_meta->unbuf) {
 			break;
 		}
 		result_meta->unbuf->eof_reached = TRUE;
-		result_meta->meta = stmt->result->meta->m->clone_metadata(stmt->result->meta);
+		result_meta->meta = stmt->result->meta->m->clone_metadata(result_meta, stmt->result->meta);
 		if (!result_meta->meta) {
 			break;
 		}
diff --git a/ext/mysqlnd/mysqlnd_result.c b/ext/mysqlnd/mysqlnd_result.c
index 99cd85749b..3e97e2497b 100644
--- a/ext/mysqlnd/mysqlnd_result.c
+++ b/ext/mysqlnd/mysqlnd_result.c
@@ -190,7 +190,7 @@ MYSQLND_METHOD(mysqlnd_result_unbuffered, free_result)(MYSQLND_RES_UNBUFFERED *
 		result->row_packet = NULL;
 	}
 
-	mysqlnd_mempool_destroy(result->result_set_memory_pool);
+	mysqlnd_mempool_restore_state(result->result_set_memory_pool);
 
 	DBG_VOID_RETURN;
 }
@@ -261,7 +261,7 @@ MYSQLND_METHOD(mysqlnd_result_buffered, free_result)(MYSQLND_RES_BUFFERED * cons
 		set->row_buffers = NULL;
 	}
 
-	mysqlnd_mempool_destroy(set->result_set_memory_pool);
+	mysqlnd_mempool_restore_state(set->result_set_memory_pool);
 
 	DBG_VOID_RETURN;
 }
@@ -320,7 +320,7 @@ void MYSQLND_METHOD(mysqlnd_res, free_result_internal)(MYSQLND_RES * result)
 		result->conn = NULL;
 	}
 
-	mnd_efree(result);
+	mysqlnd_mempool_destroy(result->memory_pool);
 
 	DBG_VOID_RETURN;
 }
@@ -344,7 +344,7 @@ MYSQLND_METHOD(mysqlnd_res, read_result_metadata)(MYSQLND_RES * result, MYSQLND_
 		result->meta = NULL;
 	}
 
-	result->meta = result->m.result_meta_init(result->field_count);
+	result->meta = result->m.result_meta_init(result, result->field_count);
 	if (!result->meta) {
 		SET_OOM_ERROR(conn->error_info);
 		DBG_RETURN(FAIL);
@@ -353,7 +353,7 @@ MYSQLND_METHOD(mysqlnd_res, read_result_metadata)(MYSQLND_RES * result, MYSQLND_
 	/* 1. Read all fields metadata */
 
 	/* It's safe to reread without freeing */
-	if (FAIL == result->meta->m->read_metadata(result->meta, conn)) {
+	if (FAIL == result->meta->m->read_metadata(result->meta, conn, result)) {
 		result->m.free_result_contents(result);
 		DBG_RETURN(FAIL);
 	}
@@ -514,7 +514,7 @@ mysqlnd_query_read_result_set_header(MYSQLND_CONN_DATA * conn, MYSQLND_STMT * s)
 				if (FAIL == (ret = PACKET_READ(conn, &fields_eof))) {
 					DBG_ERR("Error occurred while reading the EOF packet");
 					result->m.free_result_contents(result);
-					mnd_efree(result);
+					mysqlnd_mempool_destroy(result->memory_pool);
 					if (!stmt) {
 						conn->current_result = NULL;
 					} else {
@@ -906,7 +906,7 @@ MYSQLND_METHOD(mysqlnd_res, use_result)(MYSQLND_RES * const result, const zend_b
 		result->type			= MYSQLND_RES_PS_UNBUF;
 	}
 
-	result->unbuf = mysqlnd_result_unbuffered_init(result->field_count, ps);
+	result->unbuf = mysqlnd_result_unbuffered_init(result, result->field_count, ps);
 	if (!result->unbuf) {
 		goto oom;
 	}
@@ -1389,14 +1389,14 @@ MYSQLND_METHOD(mysqlnd_res, store_result)(MYSQLND_RES * result,
 	SET_CONNECTION_STATE(&conn->state, CONN_FETCHING_DATA);
 
 	if (flags & MYSQLND_STORE_NO_COPY) {
-		result->stored_data	= (MYSQLND_RES_BUFFERED *) mysqlnd_result_buffered_zval_init(result->field_count, flags & MYSQLND_STORE_PS);
+		result->stored_data	= (MYSQLND_RES_BUFFERED *) mysqlnd_result_buffered_zval_init(result, result->field_count, flags & MYSQLND_STORE_PS);
 		if (!result->stored_data) {
 			SET_OOM_ERROR(conn->error_info);
 			DBG_RETURN(NULL);
 		}
 		row_buffers = &result->stored_data->row_buffers;
 	} else if (flags & MYSQLND_STORE_COPY) {
-		result->stored_data	= (MYSQLND_RES_BUFFERED *) mysqlnd_result_buffered_c_init(result->field_count, flags & MYSQLND_STORE_PS);
+		result->stored_data	= (MYSQLND_RES_BUFFERED *) mysqlnd_result_buffered_c_init(result, result->field_count, flags & MYSQLND_STORE_PS);
 		if (!result->stored_data) {
 			SET_OOM_ERROR(conn->error_info);
 			DBG_RETURN(NULL);
@@ -1886,14 +1886,20 @@ PHPAPI MYSQLND_RES *
 mysqlnd_result_init(const unsigned int field_count)
 {
 	const size_t alloc_size = sizeof(MYSQLND_RES) + mysqlnd_plugin_count() * sizeof(void *);
-	MYSQLND_RES * ret = mnd_ecalloc(1, alloc_size);
+	MYSQLND_MEMORY_POOL * pool;
+	MYSQLND_RES * ret;
 
 	DBG_ENTER("mysqlnd_result_init");
 
-	if (!ret) {
+	pool = mysqlnd_mempool_create(MYSQLND_G(mempool_default_size));
+	if (!pool) {
 		DBG_RETURN(NULL);
 	}
 
+	ret = pool->get_chunk(pool, alloc_size);
+	memset(ret, 0, alloc_size);
+
+	ret->memory_pool	= pool;
 	ret->field_count	= field_count;
 	ret->m = *mysqlnd_result_get_methods();
 
@@ -1904,19 +1910,15 @@ mysqlnd_result_init(const unsigned int field_count)
 
 /* {{{ mysqlnd_result_unbuffered_init */
 PHPAPI MYSQLND_RES_UNBUFFERED *
-mysqlnd_result_unbuffered_init(const unsigned int field_count, const zend_bool ps)
+mysqlnd_result_unbuffered_init(MYSQLND_RES *result, const unsigned int field_count, const zend_bool ps)
 {
 	const size_t alloc_size = sizeof(MYSQLND_RES_UNBUFFERED) + mysqlnd_plugin_count() * sizeof(void *);
-	MYSQLND_MEMORY_POOL * pool;
+	MYSQLND_MEMORY_POOL * pool = result->memory_pool;
 	MYSQLND_RES_UNBUFFERED * ret;
 
 	DBG_ENTER("mysqlnd_result_unbuffered_init");
 
-	pool = mysqlnd_mempool_create(MYSQLND_G(mempool_default_size));
-	if (!pool) {
-		DBG_RETURN(NULL);
-	}
-
+	mysqlnd_mempool_save_state(pool);
 	ret = pool->get_chunk(pool, alloc_size);
 	memset(ret, 0, alloc_size);
 
@@ -1943,24 +1945,20 @@ mysqlnd_result_unbuffered_init(const unsigned int field_count, const zend_bool p
 
 /* {{{ mysqlnd_result_buffered_zval_init */
 PHPAPI MYSQLND_RES_BUFFERED_ZVAL *
-mysqlnd_result_buffered_zval_init(const unsigned int field_count, const zend_bool ps)
+mysqlnd_result_buffered_zval_init(MYSQLND_RES * result, const unsigned int field_count, const zend_bool ps)
 {
 	const size_t alloc_size = sizeof(MYSQLND_RES_BUFFERED_ZVAL) + mysqlnd_plugin_count() * sizeof(void *);
-	MYSQLND_MEMORY_POOL * pool;
+	MYSQLND_MEMORY_POOL * pool = result->memory_pool;
 	MYSQLND_RES_BUFFERED_ZVAL * ret;
 
 	DBG_ENTER("mysqlnd_result_buffered_zval_init");
 
-	pool = mysqlnd_mempool_create(MYSQLND_G(mempool_default_size));
-	if (!pool) {
-		DBG_RETURN(NULL);
-	}
-
+	mysqlnd_mempool_save_state(pool);
 	ret = pool->get_chunk(pool, alloc_size);
 	memset(ret, 0, alloc_size);
 
 	if (FAIL == mysqlnd_error_info_init(&ret->error_info, 0)) {
-		mysqlnd_mempool_destroy(pool);
+		mysqlnd_mempool_restore_state(pool);
 		DBG_RETURN(NULL);
 	}
 
@@ -1990,24 +1988,20 @@ mysqlnd_result_buffered_zval_init(const unsigned int field_count, const zend_boo
 
 /* {{{ mysqlnd_result_buffered_c_init */
 PHPAPI MYSQLND_RES_BUFFERED_C *
-mysqlnd_result_buffered_c_init(const unsigned int field_count, const zend_bool ps)
+mysqlnd_result_buffered_c_init(MYSQLND_RES * result, const unsigned int field_count, const zend_bool ps)
 {
 	const size_t alloc_size = sizeof(MYSQLND_RES_BUFFERED_C) + mysqlnd_plugin_count() * sizeof(void *);
-	MYSQLND_MEMORY_POOL * pool;
+	MYSQLND_MEMORY_POOL * pool = result->memory_pool;
 	MYSQLND_RES_BUFFERED_C * ret;
 
 	DBG_ENTER("mysqlnd_result_buffered_c_init");
 
-	pool = mysqlnd_mempool_create(MYSQLND_G(mempool_default_size));
-	if (!pool) {
-		DBG_RETURN(NULL);
-	}
-
+	mysqlnd_mempool_save_state(pool);
 	ret = pool->get_chunk(pool, alloc_size);
 	memset(ret, 0, alloc_size);
 
 	if (FAIL == mysqlnd_error_info_init(&ret->error_info, 0)) {
-		mysqlnd_mempool_destroy(pool);
+		mysqlnd_mempool_restore_state(pool);
 		DBG_RETURN(NULL);
 	}
 
diff --git a/ext/mysqlnd/mysqlnd_result.h b/ext/mysqlnd/mysqlnd_result.h
index f3b84f8508..03664e52a5 100644
--- a/ext/mysqlnd/mysqlnd_result.h
+++ b/ext/mysqlnd/mysqlnd_result.h
@@ -21,9 +21,9 @@
 #define MYSQLND_RESULT_H
 
 PHPAPI MYSQLND_RES * mysqlnd_result_init(const unsigned int field_count);
-PHPAPI MYSQLND_RES_UNBUFFERED * mysqlnd_result_unbuffered_init(const unsigned int field_count, const zend_bool ps);
-PHPAPI MYSQLND_RES_BUFFERED_ZVAL * mysqlnd_result_buffered_zval_init(const unsigned int field_count, const zend_bool ps);
-PHPAPI MYSQLND_RES_BUFFERED_C * mysqlnd_result_buffered_c_init(const unsigned int field_count, const zend_bool ps);
+PHPAPI MYSQLND_RES_UNBUFFERED * mysqlnd_result_unbuffered_init(MYSQLND_RES * result, const unsigned int field_count, const zend_bool ps);
+PHPAPI MYSQLND_RES_BUFFERED_ZVAL * mysqlnd_result_buffered_zval_init(MYSQLND_RES * result, const unsigned int field_count, const zend_bool ps);
+PHPAPI MYSQLND_RES_BUFFERED_C * mysqlnd_result_buffered_c_init(MYSQLND_RES * result, const unsigned int field_count, const zend_bool ps);
 
 enum_func_status mysqlnd_query_read_result_set_header(MYSQLND_CONN_DATA * conn, MYSQLND_STMT * stmt);
 
diff --git a/ext/mysqlnd/mysqlnd_result_meta.c b/ext/mysqlnd/mysqlnd_result_meta.c
index 1b2f4ddc33..5ff38d1f09 100644
--- a/ext/mysqlnd/mysqlnd_result_meta.c
+++ b/ext/mysqlnd/mysqlnd_result_meta.c
@@ -33,14 +33,8 @@ static void
 php_mysqlnd_free_field_metadata(MYSQLND_FIELD *meta)
 {
 	if (meta) {
-		if (meta->root) {
-			mnd_efree(meta->root);
-			meta->root = NULL;
-		}
-		if (meta->def) {
-			mnd_efree(meta->def);
-			meta->def = NULL;
-		}
+		meta->root = NULL;
+		meta->def = NULL;
 		if (meta->sname) {
 			zend_string_release(meta->sname);
 		}
@@ -50,7 +44,7 @@ php_mysqlnd_free_field_metadata(MYSQLND_FIELD *meta)
 
 /* {{{ mysqlnd_res_meta::read_metadata */
 static enum_func_status
-MYSQLND_METHOD(mysqlnd_res_meta, read_metadata)(MYSQLND_RES_METADATA * const meta, MYSQLND_CONN_DATA * conn)
+MYSQLND_METHOD(mysqlnd_res_meta, read_metadata)(MYSQLND_RES_METADATA * const meta, MYSQLND_CONN_DATA * conn, MYSQLND_RES * result)
 {
 	unsigned int i = 0;
 	MYSQLND_PACKET_RES_FIELD field_packet;
@@ -58,14 +52,13 @@ MYSQLND_METHOD(mysqlnd_res_meta, read_metadata)(MYSQLND_RES_METADATA * const met
 	DBG_ENTER("mysqlnd_res_meta::read_metadata");
 
 	conn->payload_decoder_factory->m.init_result_field_packet(&field_packet);
+	field_packet.memory_pool = result->memory_pool;
 	for (;i < meta->field_count; i++) {
 		zend_ulong idx;
 
-		if (meta->fields[i].root) {
-			/* We re-read metadata for PS */
-			mnd_efree(meta->fields[i].root);
-			meta->fields[i].root = NULL;
-		}
+		/* We re-read metadata for PS */
+		ZEND_ASSERT(meta->fields[i].root == NULL);
+		meta->fields[i].root = NULL;
 
 		field_packet.metadata = &(meta->fields[i]);
 		if (FAIL == PACKET_READ(conn, &field_packet)) {
@@ -112,12 +105,10 @@ MYSQLND_METHOD(mysqlnd_res_meta, free)(MYSQLND_RES_METADATA * meta)
 		while (i--) {
 			php_mysqlnd_free_field_metadata(fields++);
 		}
-		mnd_efree(meta->fields);
 		meta->fields = NULL;
 	}
 
 	DBG_INF("Freeing metadata structure");
-	mnd_efree(meta);
 
 	DBG_VOID_RETURN;
 }
@@ -126,7 +117,7 @@ MYSQLND_METHOD(mysqlnd_res_meta, free)(MYSQLND_RES_METADATA * meta)
 
 /* {{{ mysqlnd_res::clone_metadata */
 static MYSQLND_RES_METADATA *
-MYSQLND_METHOD(mysqlnd_res_meta, clone_metadata)(const MYSQLND_RES_METADATA * const meta)
+MYSQLND_METHOD(mysqlnd_res_meta, clone_metadata)(MYSQLND_RES * result, const MYSQLND_RES_METADATA * const meta)
 {
 	unsigned int i;
 	/* +1 is to have empty marker at the end */
@@ -136,16 +127,18 @@ MYSQLND_METHOD(mysqlnd_res_meta, clone_metadata)(const MYSQLND_RES_METADATA * co
 
 	DBG_ENTER("mysqlnd_res_meta::clone_metadata");
 
-	new_meta = mnd_ecalloc(1, sizeof(MYSQLND_RES_METADATA));
+	new_meta = result->memory_pool->get_chunk(result->memory_pool, sizeof(MYSQLND_RES_METADATA));
 	if (!new_meta) {
 		goto oom;
 	}
+	memset(new_meta, 0, sizeof(MYSQLND_RES_METADATA));
 	new_meta->m = meta->m;
 
-	new_fields = mnd_ecalloc(meta->field_count + 1, sizeof(MYSQLND_FIELD));
+	new_fields = result->memory_pool->get_chunk(result->memory_pool, (meta->field_count + 1) * sizeof(MYSQLND_FIELD));
 	if (!new_fields) {
 		goto oom;
 	}
+	memset(new_fields, 0, (meta->field_count + 1) * sizeof(MYSQLND_FIELD));
 
 	/*
 	  This will copy also the strings and the root, which we will have
@@ -154,7 +147,7 @@ MYSQLND_METHOD(mysqlnd_res_meta, clone_metadata)(const MYSQLND_RES_METADATA * co
 	memcpy(new_fields, orig_fields, (meta->field_count) * sizeof(MYSQLND_FIELD));
 	for (i = 0; i < meta->field_count; i++) {
 		/* First copy the root, then field by field adjust the pointers */
-		new_fields[i].root = mnd_emalloc(orig_fields[i].root_len);
+		new_fields[i].root = result->memory_pool->get_chunk(result->memory_pool, orig_fields[i].root_len);
 
 		if (!new_fields[i].root) {
 			goto oom;
@@ -191,7 +184,7 @@ MYSQLND_METHOD(mysqlnd_res_meta, clone_metadata)(const MYSQLND_RES_METADATA * co
 		}
 		/* def is not on the root, if allocated at all */
 		if (orig_fields[i].def) {
-			new_fields[i].def = mnd_emalloc(orig_fields[i].def_length + 1);
+			new_fields[i].def = result->memory_pool->get_chunk(result->memory_pool, orig_fields[i].def_length + 1);
 			if (!new_fields[i].def) {
 				goto oom;
 			}
@@ -292,30 +285,25 @@ MYSQLND_CLASS_METHODS_END;
 
 /* {{{ mysqlnd_result_meta_init */
 PHPAPI MYSQLND_RES_METADATA *
-mysqlnd_result_meta_init(unsigned int field_count)
+mysqlnd_result_meta_init(MYSQLND_RES *result, unsigned int field_count)
 {
 	size_t alloc_size = sizeof(MYSQLND_RES_METADATA) + mysqlnd_plugin_count() * sizeof(void *);
-	MYSQLND_RES_METADATA *ret = mnd_ecalloc(1, alloc_size);
+	MYSQLND_RES_METADATA *ret;
 	DBG_ENTER("mysqlnd_result_meta_init");
 
 	do {
-		if (!ret) {
-			break;
-		}
+		ret = result->memory_pool->get_chunk(result->memory_pool, alloc_size);
+		memset(ret, 0, alloc_size);
 		ret->m = & mysqlnd_mysqlnd_res_meta_methods;
 
 		ret->field_count = field_count;
 		/* +1 is to have empty marker at the end */
-		ret->fields = mnd_ecalloc(field_count + 1, sizeof(MYSQLND_FIELD));
-		if (!ret->fields) {
-			break;
-		}
+		alloc_size = (field_count + 1) * sizeof(MYSQLND_FIELD);
+		ret->fields = result->memory_pool->get_chunk(result->memory_pool, alloc_size);
+		memset(ret->fields, 0, alloc_size);
 		DBG_INF_FMT("meta=%p", ret);
 		DBG_RETURN(ret);
 	} while (0);
-	if (ret) {
-		ret->m->free_metadata(ret);
-	}
 	DBG_RETURN(NULL);
 }
 /* }}} */
diff --git a/ext/mysqlnd/mysqlnd_result_meta.h b/ext/mysqlnd/mysqlnd_result_meta.h
index 475795fe30..e25252aa73 100644
--- a/ext/mysqlnd/mysqlnd_result_meta.h
+++ b/ext/mysqlnd/mysqlnd_result_meta.h
@@ -21,7 +21,7 @@
 #ifndef MYSQLND_RESULT_META_H
 #define MYSQLND_RESULT_META_H
 
-PHPAPI MYSQLND_RES_METADATA * mysqlnd_result_meta_init(unsigned int field_count);
+PHPAPI MYSQLND_RES_METADATA * mysqlnd_result_meta_init(MYSQLND_RES * result, unsigned int field_count);
 PHPAPI struct st_mysqlnd_res_meta_methods * mysqlnd_result_metadata_get_methods();
 PHPAPI void ** _mysqlnd_plugin_get_plugin_result_metadata_data(const MYSQLND_RES_METADATA * meta, unsigned int plugin_id);
 
diff --git a/ext/mysqlnd/mysqlnd_structs.h b/ext/mysqlnd/mysqlnd_structs.h
index cf848246c9..f5fb94daa8 100644
--- a/ext/mysqlnd/mysqlnd_structs.h
+++ b/ext/mysqlnd/mysqlnd_structs.h
@@ -54,6 +54,7 @@ struct st_mysqlnd_memory_pool
 {
 	zend_arena		*arena;
 	void			*last;
+	void            *checkpoint;
 
 	void*	(*get_chunk)(MYSQLND_MEMORY_POOL * pool, size_t size);
 	void*	(*resize_chunk)(MYSQLND_MEMORY_POOL * pool, void * ptr, size_t old_size, size_t size);
@@ -615,7 +616,7 @@ typedef void				(*func_mysqlnd_res__free_buffered_data)(MYSQLND_RES *result);
 typedef void				(*func_mysqlnd_res__unbuffered_free_last_data)(MYSQLND_RES *result);
 
 
-typedef MYSQLND_RES_METADATA * (*func_mysqlnd_res__result_meta_init)(unsigned int field_count);
+typedef MYSQLND_RES_METADATA * (*func_mysqlnd_res__result_meta_init)(MYSQLND_RES *result, unsigned int field_count);
 
 MYSQLND_CLASS_METHODS_TYPE(mysqlnd_res)
 {
@@ -693,8 +694,8 @@ typedef const MYSQLND_FIELD *	(*func_mysqlnd_res_meta__fetch_field_direct)(const
 typedef const MYSQLND_FIELD *	(*func_mysqlnd_res_meta__fetch_fields)(MYSQLND_RES_METADATA * const meta);
 typedef MYSQLND_FIELD_OFFSET	(*func_mysqlnd_res_meta__field_tell)(const MYSQLND_RES_METADATA * const meta);
 typedef MYSQLND_FIELD_OFFSET	(*func_mysqlnd_res_meta__field_seek)(MYSQLND_RES_METADATA * const meta, const MYSQLND_FIELD_OFFSET field_offset);
-typedef enum_func_status		(*func_mysqlnd_res_meta__read_metadata)(MYSQLND_RES_METADATA * const meta, MYSQLND_CONN_DATA * conn);
-typedef MYSQLND_RES_METADATA *	(*func_mysqlnd_res_meta__clone_metadata)(const MYSQLND_RES_METADATA * const meta);
+typedef enum_func_status		(*func_mysqlnd_res_meta__read_metadata)(MYSQLND_RES_METADATA * const meta, MYSQLND_CONN_DATA * conn, MYSQLND_RES * result);
+typedef MYSQLND_RES_METADATA *	(*func_mysqlnd_res_meta__clone_metadata)(MYSQLND_RES *result, const MYSQLND_RES_METADATA * const meta);
 typedef void					(*func_mysqlnd_res_meta__free_metadata)(MYSQLND_RES_METADATA * meta);
 
 MYSQLND_CLASS_METHODS_TYPE(mysqlnd_res_meta)
@@ -1223,6 +1224,8 @@ struct st_mysqlnd_res
 	MYSQLND_RES_BUFFERED	*stored_data;
 	MYSQLND_RES_UNBUFFERED	*unbuf;
 
+	MYSQLND_MEMORY_POOL		*memory_pool;
+
 	MYSQLND_CLASS_METHODS_TYPE(mysqlnd_res) m;
 };
 
diff --git a/ext/mysqlnd/mysqlnd_wireprotocol.c b/ext/mysqlnd/mysqlnd_wireprotocol.c
index a3b1a1b13e..b7b486c349 100644
--- a/ext/mysqlnd/mysqlnd_wireprotocol.c
+++ b/ext/mysqlnd/mysqlnd_wireprotocol.c
@@ -1290,7 +1290,7 @@ php_mysqlnd_rset_field_read(MYSQLND_CONN_DATA * conn, void * _packet)
 	{
 		BAIL_IF_NO_MORE_DATA;
 		DBG_INF_FMT("Def found, length %lu", len);
-		meta->def = mnd_emalloc(len + 1);
+		meta->def = packet->memory_pool->get_chunk(packet->memory_pool, len + 1);
 		if (!meta->def) {
 			SET_OOM_ERROR(error_info);
 			DBG_RETURN(FAIL);
@@ -1301,7 +1301,7 @@ php_mysqlnd_rset_field_read(MYSQLND_CONN_DATA * conn, void * _packet)
 		p += len;
 	}
 
-	root_ptr = meta->root = mnd_emalloc(total_len);
+	root_ptr = meta->root = packet->memory_pool->get_chunk(packet->memory_pool, total_len);
 	if (!root_ptr) {
 		SET_OOM_ERROR(error_info);
 		DBG_RETURN(FAIL);
diff --git a/ext/mysqlnd/mysqlnd_wireprotocol.h b/ext/mysqlnd/mysqlnd_wireprotocol.h
index fdd26a6ca3..9455e908ad 100644
--- a/ext/mysqlnd/mysqlnd_wireprotocol.h
+++ b/ext/mysqlnd/mysqlnd_wireprotocol.h
@@ -196,6 +196,7 @@ typedef struct st_mysqlnd_packet_rset_header {
 /* Result set field packet */
 typedef struct st_mysqlnd_packet_res_field {
 	MYSQLND_PACKET_HEADER	header;
+	MYSQLND_MEMORY_POOL		*memory_pool;
 	MYSQLND_FIELD			*metadata;
 	/* For table definitions, empty for result sets */
 	zend_bool				skip_parsing;