There was two problems. Firstly, if page in ibuf is encrypted but
decrypt failed we should not allow InnoDB to start because
this means that system tablespace is encrypted and not usable.
Secondly, if page decrypt is detected we should return false
from buf_page_decrypt_after_read.
Analysis: Lengths which are not UNIV_SQL_NULL, but bigger than the following
number indicate that a field contains a reference to an externally
stored part of the field in the tablespace. The length field then
contains the sum of the following flag and the locally stored len.
This was incorrectly set to
define UNIV_EXTERN_STORAGE_FIELD (UNIV_SQL_NULL - UNIV_PAGE_SIZE_MAX)
When it should be
define UNIV_EXTERN_STORAGE_FIELD (UNIV_SQL_NULL - UNIV_PAGE_SIZE_DEF)
Additionally, we need to disable support for > 16K page size for
row compressed tables because a compressed page directory entry
reserves 14 bits for the start offset and 2 bits for flags.
This limits the uncompressed page size to 16k. To support
larger pages page directory entry needs to be larger.
Analysis: Problem was that in fil_read_first_page we do find that
table has encryption information and that encryption service
or used key_id is not available. But, then we just printed
fatal error message that causes above assertion.
Fix: When we open single table tablespace if it has encryption
information (crypt_data) store this crypt data to the table
structure. When we open a table and we find out that tablespace
is not available, check has table a encryption information
and from there is encryption service or used key_id is not available.
If it is, add additional warning for SQL-layer.
available space on disk
Add error handling when disk full situation happens and
intentionally bring server down with stacktrace because
on all cases InnoDB can't continue anyway.
innodb_stats_sample_pages
Analysis: If you set the number of analyzed pages
to very low number compared to actual pages on
that table/index it randomly pics those pages
(default 8 pages), this leads to fact that query
after analyze table returns different results. If
the index tree is small, smaller than 10 *
n_sample_pages + total_external_size, then the
estimate is ok. For bigger index trees it is
common that we do not see any borders between
key values in the few pages we pick. But still
there may be n_sample_pages different key values,
or even more. And it just tries to
approximate to n_sample_pages (8).
Fix: (1) Introduced new dynamic configuration variable
innodb_stats_sample_traditional that retains
the current design. Default false.
(2) If traditional sample is not used we use
n_sample_pages = max(min(srv_stats_sample_pages,
index->stat_index_size),
log2(index->stat_index_size)*
srv_stats_sample_pages);
(3) Introduced new dynamic configuration variable
stat_modified_counter (default = 0) if set
sets lower bound for row updates when statistics is re-estimated.
If user has provided upper bound for how many rows needs to be updated
before we calculate new statistics we use minimum of provided value
and 1/16 of table every 16th round. If no upper bound is provided
(srv_stats_modified_counter = 0, default) then calculate new statistics
if 1 / 16 of table has been modified
since the last time a statistics batch was run.
We calculate statistics at most every 16th round, since we may have
a counter table which is very small and updated very often.
@param t table
@return true if the table has changed too much and stats need to be
recalculated
*/
#define DICT_TABLE_CHANGED_TOO_MUCH(t) \
((ib_int64_t) (t)->stat_modified_counter > (srv_stats_modified_counter ? \
ut_min(srv_stats_modified_counter, (16 + (t)->stat_n_rows / 16)) : \
16 + (t)->stat_n_rows / 16))
Merge Facebook commit 25295d003cb0c17aa8fb756523923c77250b3294
authored by Steaphan Greene from https://github.com/facebook/mysql-5.6
This adds a pointer to the trx to each mtr.
This allows the trx to be accessed in parts of the code
where it was otherwise not available. This is needed later.
Analysis: Based on crashed the buffer pool instance identifier is
not correct on block to be freed. Add LRU list mutex holding
on functions calling free and add additional safety checks.
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.
