close[t:4334] merging 4334 to main. bulk fetch now grabs rows at an...

close[t:4334] merging 4334 to main. bulk fetch now grabs rows at an exponentialy rate with respect to the bulk fetch iteration, so range queries now fetch at most a factor of 2 more than they should. refs 4334


git-svn-id: file:///svn/mysql/tokudb-engine/tokudb-engine@39130 c7de825b-a66e-492c-adef-691d508d4ae1

storage/tokudb/ha_tokudb.cc

@@ -4285,6 +4285,8 @@ int ha_tokudb::prepare_index_key_scan(const uchar * key, uint key_len) {
 
     range_lock_grabbed = true;
     doing_bulk_fetch = (thd_sql_command(thd) == SQLCOM_SELECT);
+    bulk_fetch_iteration = 0;
+    rows_fetched_using_bulk_fetch = 0;
     error = 0;
 cleanup:
     if (error) {
@@ -4307,7 +4309,6 @@ void ha_tokudb::invalidate_bulk_fetch() {
     curr_range_query_buff_offset = 0;
 }
 
-
 //
 // Initializes local cursor on DB with index keynr
 // Parameters:
@@ -4982,7 +4983,22 @@ int ha_tokudb::fill_range_query_buf(
     // we want to stop under these conditions:
     //  - we overran the prelocked range
     //  - we are close to the end of the buffer
-    //
+    //  - we have fetched an exponential amount of rows with
+    //  respect to the bulk fetch iteration, which is initialized 
+    //  to 0 in index_init() and prelock_range().
+
+    rows_fetched_using_bulk_fetch++;
+    // if the iteration is less than the number of possible shifts on
+    // a 64 bit integer, check that we haven't exceeded this iterations
+    // row fetch upper bound.
+    if (bulk_fetch_iteration < HA_TOKU_BULK_FETCH_ITERATION_MAX) {
+        uint64_t row_fetch_upper_bound = 1LLU << bulk_fetch_iteration;
+        assert(row_fetch_upper_bound > 0);
+        if (rows_fetched_using_bulk_fetch >= row_fetch_upper_bound) { 
+            error = 0;
+            goto cleanup;
+        }
+    }
 
     if (bytes_used_in_range_query_buff + table_share->rec_buff_length > user_defined_size) {
         error = 0;
@@ -5059,6 +5075,7 @@ int ha_tokudb::get_next(uchar* buf, int direction) {
             //
             // call c_getf_next with purpose of filling in range_query_buff
             //
+            rows_fetched_using_bulk_fetch = 0;
             if (direction > 0) {
                 error = cursor->c_getf_next(cursor, flags,
                         smart_dbt_bf_callback, &bf_info);
@@ -5067,6 +5084,9 @@ int ha_tokudb::get_next(uchar* buf, int direction) {
                 error = cursor->c_getf_prev(cursor, flags,
                         smart_dbt_bf_callback, &bf_info);
             }
+            if (bulk_fetch_iteration < HA_TOKU_BULK_FETCH_ITERATION_MAX) {
+                bulk_fetch_iteration++;
+            }
 
             error = handle_cursor_error(error, HA_ERR_END_OF_FILE,active_index);
             if (error) { goto cleanup; }
@@ -5455,6 +5475,8 @@ int ha_tokudb::prelock_range( const key_range *start_key, const key_range *end_k
     // as of now, only do it if we are doing a select
     //
     doing_bulk_fetch = (thd_sql_command(thd) == SQLCOM_SELECT);
+    bulk_fetch_iteration = 0;
+    rows_fetched_using_bulk_fetch = 0;
 
 cleanup:
     TOKUDB_DBUG_RETURN(error);
@@ -7310,6 +7332,11 @@ int ha_tokudb::tokudb_add_index(
             );
         if (error) { goto cleanup; }
 
+        // set the bulk fetch iteration to its max so that adding an
+        // index fills the bulk fetch buffer every time. we do not
+        // want it to grow exponentially fast.
+        rows_fetched_using_bulk_fetch = 0;
+        bulk_fetch_iteration = HA_TOKU_BULK_FETCH_ITERATION_MAX;
         cursor_ret_val = tmp_cursor->c_getf_next(tmp_cursor, DB_PRELOCKED,smart_dbt_bf_callback, &bf_info);
 
         while (cursor_ret_val != DB_NOTFOUND || ((bytes_used_in_range_query_buff - curr_range_query_buff_offset) > 0)) {

storage/tokudb/ha_tokudb.h

@@ -15,7 +15,6 @@
 
 class ha_tokudb;
 
-
 typedef struct loader_context {
     THD* thd;
     char write_status_msg[200];
@@ -99,7 +98,6 @@ typedef struct st_tokudb_share {
 //
 #define HA_TOKU_CAP 0
 
-
 //
 // These are keys that will be used for retrieving metadata in status.tokudb
 // To get the version, one looks up the value associated with key hatoku_version
@@ -150,6 +148,10 @@ int tokudb_update_fun(
     void *set_extra
     );
 
+// the number of rows bulk fetched in one callback grows exponentially
+// with the bulk fetch iteration, so the max iteration is the max number
+// of shifts we can perform on a 64 bit integer.
+#define HA_TOKU_BULK_FETCH_ITERATION_MAX 63
 
 class ha_tokudb : public handler {
 private:
@@ -185,6 +187,8 @@ private:
     u_int32_t size_range_query_buff; // size of the allocated range query buffer
     u_int32_t bytes_used_in_range_query_buff; // number of bytes used in the range query buffer
     u_int32_t curr_range_query_buff_offset; // current offset into the range query buffer for queries to read
+    uint64_t bulk_fetch_iteration;
+    uint64_t rows_fetched_using_bulk_fetch;
     bool doing_bulk_fetch;
 
     //