Fix overusage of memory when the result set is empty. Then no memory will be

allocated compared to before. Also grow (realloc) the rset with 10% instead
of 33% - more reallocs but better memory usage. Of course later theres is a
realloc to shrink the rset t ofree it from unused rows but its better to
to eat too much at once.

diff --git a/ext/mysqlnd/mysqlnd_result.c b/ext/mysqlnd/mysqlnd_result.c
index 6b94e2ca9231b0db2b6c4ae1a82fd2cf3a0beb38..c6e8a2cdf2b2d54ec224d9c2059f823ff4690d40 100644 (file)
--- a/ext/mysqlnd/mysqlnd_result.c
+++ b/ext/mysqlnd/mysqlnd_result.c
@@ -214,11 +214,15 @@ void mysqlnd_free_buffered_data(MYSQLND_RES *result TSRMLS_DC)
                current_buffer->free_chunk(current_buffer, TRUE TSRMLS_CC);
        }
        DBG_INF("Freeing data & row_buffer");
-       pefree(set->data, set->persistent);
-       pefree(set->row_buffers, set->persistent);
-       set->data                       = NULL;
-       set->row_buffers        = NULL;
-       set->data_cursor        = NULL;
+       if (set->data) {
+               pefree(set->data, set->persistent);
+               set->data = NULL;
+       }
+       if (set->row_buffers) {
+               pefree(set->row_buffers, set->persistent);
+               set->row_buffers        = NULL;
+       }
+       set->data_cursor = NULL;
        set->row_count  = 0;
        if (set->qcache) {
                mysqlnd_qcache_free_cache_reference(&set->qcache);
@@ -1175,7 +1179,7 @@ mysqlnd_fetch_row_buffered(MYSQLND_RES *result, void *param, unsigned int flags,
 /* }}} */
 
 
-#define STORE_RESULT_PREALLOCATED_SET 10
+#define STORE_RESULT_PREALLOCATED_SET_IF_NOT_EMPTY 2
 
 /* {{{ mysqlnd_store_result_fetch_data */
 enum_func_status
@@ -1186,21 +1190,24 @@ mysqlnd_store_result_fetch_data(MYSQLND * const conn, MYSQLND_RES *result,
 {
        enum_func_status ret;
        php_mysql_packet_row *row_packet;
-       unsigned int next_extend = STORE_RESULT_PREALLOCATED_SET, free_rows;
+       unsigned int next_extend = STORE_RESULT_PREALLOCATED_SET_IF_NOT_EMPTY, free_rows = 1;
        MYSQLND_RES_BUFFERED *set;
 
        DBG_ENTER("mysqlnd_store_result_fetch_data");
        DBG_INF_FMT("conn=%llu binary_proto=%d to_cache=%d",
                                conn->thread_id, binary_protocol, to_cache);
 
-       free_rows = next_extend;
-
        result->stored_data     = set = mnd_pecalloc(1, sizeof(MYSQLND_RES_BUFFERED), to_cache);
-       set->row_buffers= mnd_pemalloc(STORE_RESULT_PREALLOCATED_SET * sizeof(MYSQLND_MEMORY_POOL_CHUNK *), to_cache);
+       if (free_rows) {
+               set->row_buffers = mnd_pemalloc(free_rows * sizeof(MYSQLND_MEMORY_POOL_CHUNK *), to_cache);
+       }
        set->persistent = to_cache;
        set->qcache             = to_cache? mysqlnd_qcache_get_cache_reference(conn->qcache):NULL;
        set->references = 1;
 
+       result->m.row_decoder = binary_protocol? php_mysqlnd_rowp_read_binary_protocol:
+                                                                                        php_mysqlnd_rowp_read_text_protocol;
+
        /* non-persistent */
        PACKET_INIT(row_packet, PROT_ROW_PACKET, php_mysql_packet_row *, FALSE);
        row_packet->field_count = meta->field_count;
@@ -1213,18 +1220,15 @@ mysqlnd_store_result_fetch_data(MYSQLND * const conn, MYSQLND_RES *result,
 
        while (FAIL != (ret = PACKET_READ(row_packet, conn)) && !row_packet->eof) {
                if (!free_rows) {
-                       uint64 total_rows = free_rows = next_extend = next_extend * 5 / 3; /* extend with 33% */
-                       total_rows += set->row_count;
+                       uint64 total_allocated_rows = free_rows = next_extend = next_extend * 11 / 10; /* extend with 10% */
+                       total_allocated_rows += set->row_count;
                        set->row_buffers = mnd_perealloc(set->row_buffers,
-                                                                                        total_rows * sizeof(MYSQLND_MEMORY_POOL_CHUNK *),
+                                                                                        total_allocated_rows * sizeof(MYSQLND_MEMORY_POOL_CHUNK *),
                                                                                         set->persistent);
                }
                free_rows--;
                set->row_buffers[set->row_count] = row_packet->row_buffer;
 
-               result->m.row_decoder = binary_protocol? php_mysqlnd_rowp_read_binary_protocol:
-                                                                                                php_mysqlnd_rowp_read_text_protocol;
-
                set->row_count++;
 
                /* So row_packet's destructor function won't efree() it */
@@ -1239,7 +1243,12 @@ mysqlnd_store_result_fetch_data(MYSQLND * const conn, MYSQLND_RES *result,
                */
        }
        /* Overflow ? */
-       set->data = mnd_pecalloc(set->row_count * meta->field_count, sizeof(zval *), to_cache);
+       if (set->row_count) {
+               /* if pecalloc is used valgrind barks gcc version 4.3.1 20080507 (prerelease) [gcc-4_3-branch revision 135036] (SUSE Linux) */
+               set->data = mnd_pemalloc(set->row_count * meta->field_count * sizeof(zval *), to_cache);
+               memset(set->data, 0, set->row_count * meta->field_count * sizeof(zval *));
+       }
+
        MYSQLND_INC_CONN_STATISTIC_W_VALUE(&conn->stats,
                                                                           binary_protocol? STAT_ROWS_BUFFERED_FROM_CLIENT_PS:
                                                                                                                STAT_ROWS_BUFFERED_FROM_CLIENT_NORMAL,