Analysis: Can't disable the error message because you may get database
started with incorrect log file size.
Fix: Thus only improve the error message to give more information
to users.
THE PERFORMANCE UNDER HEAVY INSERT
Problem:
There are three memset call to allocate memory for system fields
in each insert.
Solution:
Instead of calling it in 3 times, we can combine it into
one memset call. It will reduce the CPU usage under heavy insert.
Approved by Marko rb-4916
This is not yet a fix. This is change to print additional information at the point
when this assertion is going to happen. Print as much information about the pages
and index to find out why next page is not a compact format.
FAILING ASSERTION: FLEN == LEN
Problem:
Broken invariant triggered when building a unique index on a
binary column and the input data contains duplicate keys. This was broken
in debug builds only.
Fix:
Fixed length of the binary datatype can be greater than length of
the shorter prefix on which index is being created.
file storage.
Analysis: posix_fallocate was called using 0 as offset and len as
desired size. This is not optimal for SSDs.
Fix: Call posix_fallocate with correct offset i.e. current file size
and extend the file from there len bytes.
on debug build when innodb_use_fallocate=1
Analysis: There was merge error that caused additional call to
fil_node_complete_io.
Fixed by removing incorrect call and fixed calculation of extended
file size.
Problem:
In the clustered index, when an update operation is done the overall
scenario (after rb#4479) is as follows:
1. Delete mark the old record that is to be updated.
2. The old record disowns the blobs.
3. Insert the new record into clustered index.
4. For non-updated blobs, new record must own it. Verified by assert.
5. For non-updated blobs, in new record marked as inherited.
Scenario involving DB_LOCK_WAIT:
If step 3 times out, then we will skip 1 and 2 and will continue from
step 3. This skipping is achieved by the UPD_NODE_INSERT_BLOB state.
In this case, step 4 is not correct. Because of step 1, the new
record need not own the blobs. Hence the assert failure.
Solution:
The assert in step 4 is removed. Instead code is added to ensure that
the record owns the blob.
Note:
This is a regression caused by rb#4479.
rb#4571 approved by Marko
AUTO_INCREMENT_INCREMENT
Problem:
=======
When auto_increment_increment system variable decreases,
immediate next value of auto increment column is not affected.
Solution:
========
Get the previous inserted value of auto increment column by
subtracting the previous auto_increment_increment from next
auto increment value. After that calculate the current autoinc value
using newly changed auto_increment_increment variable.
Approved by Sunny [rb#4394]
Problem:
The function row_upd_changes_ord_field_binary() is used to decide whether to
use row_upd_clust_rec_by_insert() or row_upd_clust_rec(). The function
row_upd_changes_ord_field_binary() does not make use of charset information.
Based on binary comparison it decides that r1 and r2 differ in their ordering
fields.
In the function row_upd_clust_rec_by_insert(), an update is done by delete +
insert. These operations internally make use of cmp_dtuple_rec_with_match()
to compare records r1 and r2. This comparison takes place with the use of
charset information.
This means that it is possible for the deleted record to be reused in the
subsequent insert. In the given scenario, the characters 'a' and 'A' are
considered equal in the my_charset_latin1. When this happens, the ownership
information of externally stored blobs are not correctly handled.
Solution:
When an update is done by delete followed by insert, disown the relevant
externally stored fields during the delete marking itself (within the same
mtr). If the insert succeeds, then nothing with respect to blob ownership
needs to be done. If the insert fails, then the disown done earlier will be
removed when the operation is rolled back.
rb#4479 approved by Marko.
The maximum value for innodb_thread_sleep_delay is 4294967295 (32-bit) or
18446744073709551615 (64-bit) microseconds. This is way too big, since
the max value of innodb_thread_sleep_delay is limited by
innodb_adaptive_max_sleep_delay if that value is set to non-zero value
(its default is 150,000).
Solution
The maximum value of innodb_thread_sleep_delay should be the same as
the maximum value of innodb_adaptive_max_sleep_delay, which is 1000000.
Approved by Jimmy, rb#4429
IN DOCUMENTATION
Problem
-------
The documentation says that we support 'K' prefix
while specifiying size for innodb datafile in the
server variable for innodb_data_file_path ,but the
function srv_parse_megabytes() only handles only
'M' (megabytes) and 'G' (gigabytes) .
Fix
---
Modify srv_parse_megabytes() to handle Kilobytes.
Add in documentation that while specifying size
in KB it should be mentioned in multiples of 1024
other wise they will be rounded off to nearest
MB (megabyte) boundry .(eg if size mentioned
as 2313KB will be considered as 2 MB ).
[ Approved by Marko #rb 2387 ]
ERRORS IN THE FK SECTION
ANALYSIS
--------
Any error during the renaming of the table was
incorrectly logged in the dict_foreign_err_file
and it showed up in foreign key section when
we give the query "show engine innodb status".
FIX
---
Prevent renaming error from being logged in
dict_foreign_err_file section.
[Aprooved by marko #rb 2501 ]
possibly since it was introduced in the patch for Bug#16720368 around
2013-04-30. This fix is simply to adjust the mtr.add_suppression() lines
in the testcase and to add a missing "\n" in the error message.
Approved by Marko in RB 3746
Regression from bug#14621190 due to disabled optimistic restoration
of cursor, which required full key lookup instead of verifying
if previously positioned btree cursor could be reused.
Fixed by enable optimistic restore and adjust cursor afterward.
rb#3324 approved by Marko.
--Implemented CHECK TABLE...QUICK.
Introduce CHECK TABLE...QUICK that would skip the btr_validate_index()
and btr_search_validate() call, and count the no. of records in each index.
Approved by Marko and Kevin. (rb#3567).
AND 'KILL SESSION' LEAD TO CRASH
Analysis:
--------
This situation occurs when the connection executes query
"show engine innodb status" and this connection is killed by
executing statement "kill <con>" by another connection.
In function "innodb_show_status", function "stat_print"
is called to print the status but return value of function
is not checked. After killing connection, if write to
connection fails then error is returned and same is set
in Diagnostic area. Since FALSE is returned from
"innodb_show_status" now, assert to check no error
is set in function "set_eof_status" (called from
my_eof) is failing.
Fix:
----
Changed code to check return value of function "stat_print"
in "innodb_show_status".
ha_innobase::records_in_range() should return HA_POS_ERROR for the table during discarded without requesting pages.
The later other handler method should treat the error correctly.
Approved by Sunny in rb#3433
INDEX_READ_MAP HAD NO MATCH
If index_read_map is called for exact search and no matching records
exists it will position the cursor on the next record, but still having the
relative position to BTR_PCUR_ON.
This will make a call for index_next to read yet another next record,
instead of returning the record the cursor points to.
Fixed by setting pcur->rel_pos = BTR_PCUR_BEFORE if an exact
[prefix] search is done, but failed.
Also avoids optimistic restoration if rel_pos != BTR_PCUR_ON,
since btr_cur may be different than old_rec.
rb#3324, approved by Marko and Jimmy
The testcase for this bug fails randomly due to two reasons.
1. Due to ibuf merge happening background
2. Due to dict stats update which brings the evicted page back into
buffer pool.
Fix ibuf_contract_ext() to not do any merges with ibuf_debug enabled and
also changed dict_stats_update() to return fake statistics without
bringing the secondary index pages into buffer pool.
Approved by Marko. rb#3419
IT IS DONE IN-PLACE
With change buffer enabled, InnoDB doesn't write a transaction log
record when it merges a record from the insert buffer to an secondary
index page if the insertion is performed as an update-in-place.
Fixed by logging the 'update-in-place' operation on secondary index
pages.
Approved by Marko. rb#2429
