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connectors experimental galera main
Vladislav Vaintroub
MDEV-37556 Memory leak in proxy protocol with name resolution enabled

When proxy protocol is used and --skip-name-resolve is not set,
thd_set_peer_addr() is called twice per connection: once for the real TCP peer (in check_connection),
and again for the proxied address (in handle_proxy_header).
Each call invokes ip_to_hostname(), which allocates a hostname string
(unless loopback connection is used) and stores it as
thd->main_security_ctx.host. That code missed to free previously
allocated hostname, which results into memory leak.

This is now fixed. Also added debug-only test to mysql_client_test, which
fakes DNS and IP resolution the same way some perfschema tests do, to
emulate remote TCP connection in MTR.
Oleg Smirnov
Enable release builds
bsrikanth-mariadb
run replay_server_test only if --replay-server is provided

if --replay-server option is not provided, then the test is skipped.
Oleg Smirnov
Enable re-split of marked chunks
Raghunandan Bhat
MDEV-39559: Assertion `b` failed in `my_strnncoll_xxxx_nopad_ci`

Problem:
  When verifying a `UNIQUE` constraint over an empty BLOB/TEXT column,
  `Field_blob::cmp(a_ptr, b_ptr)` extracts a NULL data pointer (with
  length 0) from the record slot and forwards it to the charset-level
  comparison, which asserts non-NULL pointers (added in MDEV-35717).

  A zero-length blob is allowed to have a NULL data pointer in its
  record slot; `Field_blob::val_decimal()` already treats (NULL, 0) as
  an empty value. The comparison paths missed that substitution.

Fix:
  - In `Field_blob::cmp(a_ptr, b_ptr)`, `Field_blob::cmp_prefix()` and
    `Field_blob::key_cmp(key_ptr, max_key_length)`, substitute "" for a
    NULL data pointer before delegating to the comparison.
  - Add a debug assert in each of the above functions to document the
    invariant that a NULL pointer is only valid alongside zero length
    and (NULL, length>0) is invalid.
Oleg Smirnov
Enable InnoDB pre-fetcher for parallel scans
Rex Johnston
MDEV-39859 Remove per worker tmp tables, ship raw records to manager
Oleg Smirnov
Fix failing tests
Rex Johnston
MDEV-39495 Parallel Query: Use temporary work tables to ship results: basic test

Built on top of MDEV-39492, the parallel worker manager creates N
temporary tables and gives them to each parallel worker to populate.
At the conclusion of all worker threads, each row from the above tables
is added to the join_tab->table representing the query result.  To use

MariaDB [test]> set session parallel_worker_threads=10;
Query OK, 0 rows affected (0.001 sec)

MariaDB [test]> select SQL_BUFFER_RESULT * from t1 join seq_1_to_5 on t1.a = seq;
+------+------+-----+
| a    | b    | seq |
+------+------+-----+
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
|    1 | one  |  1 |
|    2 | two  |  2 |
|    1 | un  |  1 |
+------+------+-----+
30 rows in set (0.010 sec)

Each worker has read the first table with a JT_ALL access method and
replicated the results back to the manager thread, which executes the
rest of the join.  In the above example there are 10 worker threads, so
10 copies of the join result.

MDEV-39859 alter parallel scan costs to favour putting table first.
Pekka Lampio
MDEV-38386 Fix incomplete cleanup in Galera MTR tests failing under --repeat

A number of Galera MTR tests pass on the first run but fail on a second
--repeat iteration, because server, cluster or filesystem state leaks
across runs and the test does not restore a clean starting state.

Fix the cleanup (or force a fresh cluster) in the affected tests. Each
fix was verified with --repeat=2 --force.

1. Stale async-slave GTID position (11 tests)

  RESET SLAVE [ALL] does not clear gtid_slave_pos. As the master does
  RESET MASTER in cleanup, on the next run the slave considers the
  events already applied and skips them, so the replicated tables never
  appear. Clear the position with SET GLOBAL gtid_slave_pos = "".

2. Leftover binlog GTID state from trailing cleanup (1 test)

  Trailing DROP TABLE / mtr.add_suppression statements ran after the
  .inc's reset master and re-populated node_2's binlog. gtid_binlog_state
  keeps the latest seqno per (domain, server_id) pair, so a stray
  0-2-<n> survived into the next run and broke the state comparison.
  Reorder the cleanup and reset node_2's binlog last.

3. Cluster-global, one-time or time-window state (11 tests)

  The wsrep GTID domain seqno is cluster-global and is not reset by
  reset master (nor by a mid-test SST rejoin); error-log contents,
  warning-flood suppression timers and one-time bootstrap behaviour are
  likewise not restored by in-test cleanup. Force a fresh cluster with
  include/force_restart.inc.

4. Leftover filesystem artifacts (1 test)

  mariabackup refuses to back up into a non-empty target directory, so
  the leftover target dirs from the previous run made the backup fail
  silently and the expected log messages never appeared. Remove the
  target directories in cleanup.
Rucha Deodhar
MDEV-34723: NEW and OLD in a trigger as row variables

Implementation:
NEW and OLD represent the entire table row. So it can be thought of as
list of Item_trigger_field. When we are in a trigger and NEW or OLD is
encountered, create Item_trigger_row object with same constructor as
Item_trigger_field, it will also be used later while creating
Item_trigger_field objects. Populate the m_fields list while
fixing fields. Create a corresponding instruction sp_instr_set_trigger_row
which will be used to set the values
Vladislav Vaintroub
MDEV-37556 Memory leak in proxy protocol with name resolution enabled

When proxy protocol is used and --skip-name-resolve is not set,
thd_set_peer_addr() is called twice per connection: once for the real TCP peer (in check_connection),
and again for the proxied address (in handle_proxy_header).
Each call invokes ip_to_hostname(), which allocates a hostname string
(unless loopback connection is used) and stores it as
thd->main_security_ctx.host. That code missed to free previously
allocated hostname, which results into memory leak.

This is now fixed. Also added debug-only test to mysql_client_test, which
fakes DNS and IP resolution the same way some perfschema tests do, to
emulate remote TCP connection in MTR.
Dave Gosselin
MDEV-39207:  mark test as not_embedded

Test fails on embedded CI because original not_embedded flag was not preserved
Dave Gosselin
MDEV-39207:  mark test as not_embedded

Test fails on embedded CI because original not_embedded flag was not preserved
Oleg Smirnov
Enable InnoDB pre-fetcher for parallel scans
Daniel Black
MDEV-31209 Queries with window functions do not obey KILL / max_statement_time

Window functions run in a loop in
Frame_cursor::compute_values_for_current_row which can include a large
number of rows.

Adjust this function to check for the current thd being killed by only
every 256 rows, so as not to destroy any CPU pipelining or similar.
Varun Deep Saini
MDEV-25727 Add FORMAT JSON support to JSON_TABLE

Allow explicit FORMAT JSON columns in JSON_TABLE for supported
string, blob, and JSON targets.

Preserve the explicit clause in view printing and add regression
coverage for formatted extraction, unsupported targets, and SHOW
CREATE VIEW.

Signed-off-by: Varun Deep Saini <[email protected]>
Signed-off-by: Varun Deep Saini <[email protected]>
Mohammad Tafzeel Shams
MDEV-38305: Expose adaptive hash index statistics in ANALYZE FORMAT=JSON

Expose InnoDB's Adaptive Hash Index (AHI) statistics through ANALYZE
FORMAT=JSON output and global status variables to provide query-level
and system-level visibility into AHI usage and effectiveness.
This allows DBAs and developers to monitor how well
the adaptive hash index is serving their workloads on a per-query basis.

The r_ahi_stats object (nested inside r_engine_stats) now reports four
key metrics: ahi_searches (successful AHI lookups), ahi_searches_btree
(AHI misses requiring B-tree fallback), ahi_rows_added (rows inserted
into AHI), and ahi_pages_added (pages indexed by AHI). These same
metrics are exposed globally via innodb_status_variables.

Transaction-local tracking eliminates contention by accumulating
statistics in trx_t fields (n_sea, n_non_sea, n_ahi_rows_added,
n_ahi_pages_added) and aggregating them into global atomic counters
during trx_t::commit_cleanup() and trx_t::free(),
following the pattern established for buf_pool.stat.n_page_gets.

AHI counters are now organized as data members of the btr_sea structure
where they logically belong, using anonymous unions to enable both
atomic writes and direct non-atomic reads.

- btr_ahi_inc_searches(): Increment trx->n_sea when AHI lookup succeeds.
- btr_ahi_inc_searches_btree(): Increment trx->n_non_sea when AHI lookup
  fails and falls back to B-tree search.
- btr_ahi_inc_rows_added(): Increment trx->n_ahi_rows_added when rows
  are added to the adaptive hash index structure.
- btr_ahi_inc_pages_added(): Increment trx->n_ahi_pages_added when new
  pages are indexed by AHI.
- btr_cur_t::search_leaf(): Call btr_ahi_inc_searches() on successful
  AHI hit and btr_ahi_inc_searches_btree() on AHI miss.
- btr_sea: Add four counter members with anonymous unions to allow atomic
  writes and lockless reads: hit_count/hit_count_nonatomic (successful AHI
  lookups), miss_count/miss_count_nonatomic (B-tree searches after AHI miss),
  rows_added/rows_added_nonatomic (rows added to AHI), and
  pages_added/pages_added_nonatomic (pages added to AHI). Also includes
  hit_count_old and miss_count_old variant for computing deltas in monitor
  output.
- btr0cur.h/btr0cur.cc: Remove global declarations and definitions of
  btr_cur_n_sea, btr_cur_n_non_sea, btr_cur_n_sea_old, btr_cur_n_non_sea_old,
  btr_ahi_n_rows_added, and btr_ahi_n_pages_added as they are now data
  members of btr_sea.
- export_var_t: Remove innodb_ahi_hit, innodb_ahi_miss, innodb_ahi_rows_added,
  and innodb_ahi_pages_added members. MySQL status variables now point
  directly to btr_search counters.
- innodb_status_variables[]: Change AHI status variable pointers from
  &export_vars.innodb_ahi_* to &btr_search.*_nonatomic, enabling zero-copy
  reads: adaptive_hash_hash_searches points to &btr_search.hit_count_nonatomic,
  adaptive_hash_non_hash_searches to &btr_search.miss_count_nonatomic,
  adaptive_hash_rows_added to &btr_search.rows_added_nonatomic, and
  adaptive_hash_pages_added to &btr_search.pages_added_nonatomic.
- MONITOR_OVLD_ADAPTIVE_HASH_ROW_ADDED, MONITOR_OVLD_ADAPTIVE_HASH_PAGE_ADDED:
  Convert monitor counters to "overload" type that read from atomic counters
  btr_search.rows_added and btr_search.pages_added respectively instead of
  maintaining separate statistics.
- trx_t::commit_cleanup() and trx_t::free(): Update transaction cleanup to
  increment btr_search.hit_count, btr_search.miss_count, btr_search.rows_added,
  and btr_search.pages_added instead of the old global counters.
- trace_engine_stats(): Output r_ahi_stats object with all four AHI
  counters in JSON format when any AHI activity is detected during query
  execution.
- ha_handler_stats: Added ahi_searches, ahi_searches_btree, ahi_rows_added,
  and ahi_pages_added fields to track per-query AHI statistics.
- Add mtr parameter to btr_search_move_or_delete_hash_entries(),
  btr_cur_t::search_info_update(), btr_search_update_hash_on_insert(),
  btr_search_update_hash_ref(), btr_search_info_update_hash(), and
  btr_search_build_page_hash_index() to allow updating AHI statistics.
- ahi_stats.test: Comprehensive verification of AHI statistics reporting
  across different scenarios: insufficient accesses (no AHI build),
  threshold triggering (AHI construction), heavy warmup (full AHI
  utilization), and disabled AHI (verify zero statistics).
- check_ahi_status.inc: Reusable include file for executing queries with
  configurable warmup repetitions and extracting AHI statistics from
  ANALYZE FORMAT=JSON output using JSON path expressions.
Sergei Petrunia
Make mtr accept and ignore  "--disable_replay next_query|test_file text" command
Fariha Shaikh
MDEV-39928 Fix GitLab CI centos9 job failure

The centos9 job uses yum-builddep -y mariadb-server to install build
dependencies, but the mariadb-server source package has been removed
from CentOS Stream 9 repositories. Replace with explicit installation of
the required build dependencies.

All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer Amazon Web
Services, Inc.
Raghunandan Bhat
MDEV-39559: Assertion `b` failed in `my_strnncoll_xxxx_nopad_ci`

Problem:
  When verifying a `UNIQUE` constraint over an empty BLOB/TEXT column,
  `Field_blob::cmp(a_ptr, b_ptr)` extracts a NULL data pointer (with
  length 0) from the record slot and forwards it to the charset-level
  comparison, which asserts non-NULL pointers (added in MDEV-35717).

  A zero-length blob is allowed to have a NULL data pointer in its
  record slot; `Field_blob::val_decimal()` already treats (NULL, 0) as
  an empty value. The comparison paths missed that substitution.

Fix:
  - In `Field_blob::cmp(a_ptr, b_ptr)`, `Field_blob::cmp_prefix()` and
    `Field_blob::key_cmp(key_ptr, max_key_length)`, substitute "" for a
    NULL data pointer before delegating to the comparison.
  - Add a debug assert in each of the above functions to document the
    invariant that a NULL pointer is only valid alongside zero length
    and (NULL, length>0) is invalid.
Yuchen Pei
MDEV-32796 [demo] federatedx suffers the same problem as spider
Oleg Smirnov
Enable re-split of marked chunks
Yuchen Pei
MDEV-15621 Auto add RANGE COLUMNS partitions by interval

Allow auto partitioning by interval in PARTITION BY RANGE COLUMNS

PARTITION BY RANGE COLUMNS (col_name)
INTERVAL interval [AUTO]
(
  PARTITION partition_name VALUES LESS THAN (value)
  [, PARTITION partition_name VALUES LESS THAN (value) ... ]
)

where

- col_name is the name of one column of type DATE or DATETIME or
  TIMESTAMP

- at least one partition is supplied, and the highest partition cannot
  have MAXVALUE range

- INTERVAL interval is a positive time interval. it can be mariadb
  format or oracle NUMTODSINTERVAL/NUMTOYMINTERVAL format. Like
  versioning, the smallest unit is second, i.e. no subsecond like
  microsecond.

- DATE column cannot have interval with values less than a day

- Subpartitions are allowed, but restricted to existing subpartition
  types, i.e. [LINEAR] (KEY|HASH)

When performing one of the following DML statements on such a table,
it will first add partitions by the specified interval until the
partition covers the current time:

- INSERT
- INSERT ... SELECT
- LOAD
- UPDATE
- REPLACE
- REPLACE ... SELECT

Partition addition will not cause an implicit commit like DDL normally
does.

The partitions are named pN.

Otherwise the table behaves exactly the same as a normal RANGE COLUMNS
partitioned table.

Note that TIMESTAMP is not allowed as a type for PARTITION BY RANGE
COLUMNS otherwise.
Alexander Barkov
MDEV-39518 Allow prepared statements in stored functions in assignment right hand

In progress
Rex Johnston
MDEV-39492 Parallel Query: Study how to create worker threads

Introduces parallel_worker_threads variable to control the number
of worker threads created by a parallel execution query.

2 new files, sql_parallel_workers.h sql_parallel_workers.cc which
contain structures for the creation, management and deletion of
parallel worker threads (pwt_ in the name).  Main management
class created in the stack in JOIN::exec, implemented for the
top level select.

Current parallel_worker_thread_func sleeps for 10 seconds, generates
a warning, signals the main thread, sleeps 10 seconds, signals the
main thread again, sets it's finished flag and cleans it's THD.

The main thread loops through worker threads, looking for finished
thread and cleans them up if they have finished.
It then waits for a signal, then processes it's message queue.

Threads are registed in server_threads, so are visible in
information_schema.processlist and the show processlist command.

We check that a kill query on a parallel worker is passed onto it's
manager and the query is properly aborted, and that a kill connection
is handled properly in parallel_worker.test.

Review input 1: cleanup earlier

Do cleanup before we've finished sending the result to the client.
This way, one can see the errors (and eventually warnings) marshalled
back to the main thread and returned to the user:

MariaDB [test]> set parallel_worker_threads=10;
Query OK, 0 rows affected (0.001 sec)

MariaDB [test]> select seq from seq_1_to_10;
ERROR 4103 (HY000): Argument to the worker_busted_function() function does not belong to the range [0,1]

Assisted by Sergei Petrunia and Claude Code.
Sergei Petrunia
Revert the --replay-server mtr feature
Rex Johnston
MDEV-39495 Parallel Query:comments and code cleanup
Dave Gosselin
MDEV-38158:  Incorrect query result

When setup_copy_fields() needs to copy a non-aggregate function value,
it doesn't construct an Item_copy directly.  Instead, it calls
Type_handler::create_item_copy, which is a kind of factory.  The base
Type_handler::create_item_copy returns Item_copy_string.  Some type
handlers override it, like timestamp and fixed binary.  However, the
numeric type handlers (e.g., float, double, int, decimal) did not, so
they fell through to that base and got Item_copy_string.

A SELECT that aggregates will copy each non aggregate function value
into a temporary table through an Item_copy object, whose concrete
type is chosen by the create_item_copy method on the value's type
handler.  For numeric types that method returned Item_copy_string,
which stores the value as text.  A FLOAT keeps only FLT_DIG
significant digits as text, too few to reproduce its 24 bit mantissa,
so the copied value differed from the original.  With one row per
group, CAST(c1 AS FLOAT) - MIN(CAST(c1 AS FLOAT)) returned a large
number instead of zero.

Add Item_copy_real with Item_copy_float and Item_copy_double variants
that keep the value as a double, the same way Item_cache_real does, and
let the float and double type handlers create them.  This mirrors the
existing copy items for timestamp and fixed binary types.
Oleg Smirnov
WIP: Split InnoDB table into chunks and process chunks one by one in parallel scan manner
Rex Johnston
MDEV-39495 Parallel Query:comments and code cleanup
Oleg Smirnov
Enable re-split of marked chunks
Oleg Smirnov
Enable release builds
Mohammad Tafzeel Shams
MDEV-38305: Expose adaptive hash index statistics in ANALYZE FORMAT=JSON

Expose InnoDB's Adaptive Hash Index (AHI) statistics through ANALYZE
FORMAT=JSON output and global status variables to provide query-level
and system-level visibility into AHI usage and effectiveness.
This allows DBAs and developers to monitor how well
the adaptive hash index is serving their workloads on a per-query basis.

The r_ahi_stats object (nested inside r_engine_stats) now reports four
key metrics: ahi_searches (successful AHI lookups), ahi_searches_btree
(AHI misses requiring B-tree fallback), ahi_rows_added (rows inserted
into AHI), and ahi_pages_added (pages indexed by AHI). These same
metrics are exposed globally via innodb_status_variables.

Transaction-local tracking eliminates contention by accumulating
statistics in trx_t fields (n_sea, n_non_sea, n_ahi_rows_added,
n_ahi_pages_added) and aggregating them into global atomic counters
during trx_t::commit_cleanup() and trx_t::free(),
following the pattern established for buf_pool.stat.n_page_gets.

AHI counters are now organized as data members of the btr_sea structure
where they logically belong, using anonymous unions to enable both
atomic writes and direct non-atomic reads.

- btr_ahi_inc_searches(): Increment trx->n_sea when AHI lookup succeeds.
- btr_ahi_inc_searches_btree(): Increment trx->n_non_sea when AHI lookup
  fails and falls back to B-tree search.
- btr_ahi_inc_rows_added(): Increment trx->n_ahi_rows_added when rows
  are added to the adaptive hash index structure.
- btr_ahi_inc_pages_added(): Increment trx->n_ahi_pages_added when new
  pages are indexed by AHI.
- btr_cur_t::search_leaf(): Call btr_ahi_inc_searches() on successful
  AHI hit and btr_ahi_inc_searches_btree() on AHI miss.
- btr_sea: Add four counter members with anonymous unions to allow atomic
  writes and lockless reads: hit_count/hit_count_nonatomic (successful AHI
  lookups), miss_count/miss_count_nonatomic (B-tree searches after AHI miss),
  rows_added/rows_added_nonatomic (rows added to AHI), and
  pages_added/pages_added_nonatomic (pages added to AHI). Also includes
  hit_count_old and miss_count_old variant for computing deltas in monitor
  output.
- btr0cur.h/btr0cur.cc: Remove global declarations and definitions of
  btr_cur_n_sea, btr_cur_n_non_sea, btr_cur_n_sea_old, btr_cur_n_non_sea_old,
  btr_ahi_n_rows_added, and btr_ahi_n_pages_added as they are now data
  members of btr_sea.
- export_var_t: Remove innodb_ahi_hit, innodb_ahi_miss, innodb_ahi_rows_added,
  and innodb_ahi_pages_added members. MySQL status variables now point
  directly to btr_search counters.
- innodb_status_variables[]: Change AHI status variable pointers from
  &export_vars.innodb_ahi_* to &btr_search.*_nonatomic, enabling zero-copy
  reads: adaptive_hash_hash_searches points to &btr_search.hit_count_nonatomic,
  adaptive_hash_non_hash_searches to &btr_search.miss_count_nonatomic,
  adaptive_hash_rows_added to &btr_search.rows_added_nonatomic, and
  adaptive_hash_pages_added to &btr_search.pages_added_nonatomic.
- MONITOR_OVLD_ADAPTIVE_HASH_ROW_ADDED, MONITOR_OVLD_ADAPTIVE_HASH_PAGE_ADDED:
  Convert monitor counters to "overload" type that read from atomic counters
  btr_search.rows_added and btr_search.pages_added respectively instead of
  maintaining separate statistics.
- trx_t::commit_cleanup() and trx_t::free(): Update transaction cleanup to
  increment btr_search.hit_count, btr_search.miss_count, btr_search.rows_added,
  and btr_search.pages_added instead of the old global counters.
- trace_engine_stats(): Output r_ahi_stats object with all four AHI
  counters in JSON format when any AHI activity is detected during query
  execution.
- ha_handler_stats: Added ahi_searches, ahi_searches_btree, ahi_rows_added,
  and ahi_pages_added fields to track per-query AHI statistics.
- Add mtr parameter to btr_search_move_or_delete_hash_entries(),
  btr_cur_t::search_info_update(), btr_search_update_hash_on_insert(),
  btr_search_update_hash_ref(), btr_search_info_update_hash(), and
  btr_search_build_page_hash_index() to allow updating AHI statistics.
- ahi_stats.test: Comprehensive verification of AHI statistics reporting
  across different scenarios: insufficient accesses (no AHI build),
  threshold triggering (AHI construction), heavy warmup (full AHI
  utilization), and disabled AHI (verify zero statistics).
- check_ahi_status.inc: Reusable include file for executing queries with
  configurable warmup repetitions and extracting AHI statistics from
  ANALYZE FORMAT=JSON output using JSON path expressions.
Rex Johnston
MDEV-39859 Remove per worker tmp tables, ship raw records to manager
Oleg Smirnov
Enable release builds
Oleg Smirnov
WIP: Integrate chunked InnoDB scan with parallel workers framework
Rucha Deodhar
MDEV-39878: JSON_ARRAY_INTERSECT: nested call JSON_ARRAY_INTERSECT(
JSON_ARRAY_INTERSECT(a,b), b) returns NULL instead of intersect result

Analysis:
Evaluating args[0] inside fix_length_and_dec() forces the argument to run
during the query preparation phase. If args[0] is a nested function,
its runtime memory structures are not yet initialized. This causes a
early failure that makes inner function as NULL before the query
starts executing.

Fix:
Wrap the evaluation in a const_item() check so it only runs during setup
if the argument is a constant. Otherwise, do it in runtime.
Sergei Petrunia
Make mtr accept and ignore  "--disable_replay next_query|test_file text" command
Oleg Smirnov
Enable InnoDB pre-fetcher for parallel scans