Rather than innodb_buffer_pool_dump_pct referring to the percentage of hot data
in the buffer pool, it refers to the entire buffer pool size. This means that a
completed load followed by a shutdown will write the exact same data.
The problem was:
With innodb_buffer_pool_dump_pct say 25% (the default since 10.2.2), a server
started will restore 25% of the buffer pool size with the expectation that over
time the rest of the buffer pool will be populated. Then on shutdown 25% will
be saved.
If a server is started and then is shutdown a) without much activity occurring
b) is started as a hot spare and shutdown before being used, then 6.25% (25%
of 25%) of the buffer pool is saved.
This will generate bigger dump files for users who don't have a full
innodb_buffer_pool however a realistic scenario is a buffer pool should be
completely used.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>
buf_block_init(): Initialize buf_page_t::flush_type.
For some reason, Valgrind 3.12.0 would seem to flag some
bits in adjacent bitfields as uninitialized, even though only
the two bits of flush_type were left uninitialized. Initialize
the field to get rid of many warnings.
buf_page_init_low(): Initialize buf_page_t::old.
For some reason, Valgrind 3.12.0 would seem to flag all 32
bits uninitialized when buf_page_init_for_read() invokes
buf_LRU_add_block(bpage, TRUE). This would trigger bogus warnings
for buf_page_t::freed_page_clock being uninitialized.
(The V-bits would later claim that only "old" is initialized
in the 32-bit word.) Perhaps recent compilers
(GCC 6.2.1 and clang 4.0.0) generate more optimized x86_64 code
for bitfield operations, confusing Valgrind?
mach_write_to_1(), mach_write_to_2(), mach_write_to_3():
Rewrite the assertions that ensure that the most significant
bits are zero. Apparently, clang 4.0.0 would optimize expressions
of the form ((n | 0xFF) <= 0x100) to (n <= 0x100). The redundant
0xFF was added in the first place in order to suppress a
Valgrind warning. (Valgrind would warn about comparing uninitialized
values even in the case when the uninitialized bits do not affect
the result of the comparison.)
buf_block_init(): Initialize buf_page_t::flush_type.
For some reason, Valgrind 3.12.0 would seem to flag some
bits in adjacent bitfields as uninitialized, even though only
the two bits of flush_type were left uninitialized. Initialize
the field to get rid of many warnings.
buf_page_init_low(): Initialize buf_page_t::old.
For some reason, Valgrind 3.12.0 would seem to flag all 32
bits uninitialized when buf_page_init_for_read() invokes
buf_LRU_add_block(bpage, TRUE). This would trigger bogus warnings
for buf_page_t::freed_page_clock being uninitialized.
(The V-bits would later claim that only "old" is initialized
in the 32-bit word.) Perhaps recent compilers
(GCC 6.2.1 and clang 4.0.0) generate more optimized x86_64 code
for bitfield operations, confusing Valgrind?
mach_write_to_1(), mach_write_to_2(), mach_write_to_3():
Rewrite the assertions that ensure that the most significant
bits are zero. Apparently, clang 4.0.0 would optimize expressions
of the form ((n | 0xFF) <= 0x100) to (n <= 0x100). The redundant
0xFF was added in the first place in order to suppress a
Valgrind warning. (Valgrind would warn about comparing uninitialized
values even in the case when the uninitialized bits do not affect
the result of the comparison.)
Issue:
======
Currently the approach we take to find the chunk corresponding to a given
pointer uses srv_buf_pool_chunk_unit based on the assumption that
srv_buf_pool_chunk_unit is the total size of all pages in a buffer pool
chunk. We first step back by srv_buf_pool_chunk_unit bytes and use
std::map::upper_bound() to find the first chunk in the map whose key >= the
resulting pointer.
However, the real size of a chunk (and thus, the total size of its pages)
may differ from the value configured with innodb_buffer_pool_chunk_size
due to rounding up to the OS page size. So, in some cases the above logic
gives us the wrong chunk.
Fix:
====
We find out the chunk corresponding to the give pointer without using
srv_buf_pool_chunk_unit. This is done by using std::map::upper_bound()
to find the next chunk in the map which appears right after the pointer and
decrementing the iterator, which would give us the chunk the pointer
belongs to.
Contribution by Alexey Kopytov.
RB: 13347
Reviewed-by: Debarun Banerjee <debarun.banerjee@oracle.com>
Analysis: Problem is that page is encrypted but encryption information
on page 0 has already being changed.
Fix: If page header contains key_version != 0 and even if based on
current encryption information tablespace is not encrypted we
need to check is page corrupted. If it is not, then we know that
page is not encrypted. If page is corrupted, we need to try to
decrypt it and then compare the stored and calculated checksums
to see is page corrupted or not.
Two problems:
(1) When pushing warning to sql-layer we need to check that thd != NULL
to avoid NULL-pointer reference.
(2) At tablespace key rotation if used key_id is not found from
encryption plugin tablespace should not be rotated.
MDEV-10394: Innodb system table space corrupted
Analysis: After we have read the page in buf_page_io_complete try to
find if the page is encrypted or corrupted. Encryption was determined
by reading FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION field from FIL-header
as a key_version. However, this field is not always zero even when
encryption is not used. Thus, incorrect key_version could lead situation where
decryption is tried to page that is not encrypted.
Fix: We still read key_version information from FIL_PAGE_FILE_FLUSH_LSN_OR_KEY_VERSION
field but also check if tablespace has encryption information before trying
encrypt the page.
No point to issue RELEASE memory barrier in os_thread_create_func(): thread
creation is full memory barrier.
No point to issue os_wmb in rw_lock_set_waiter_flag() and
rw_lock_reset_waiter_flag(): this is deadcode and it is unlikely operational
anyway. If atomic builtins are unavailable - memory barriers are most certainly
unavailable too.
RELEASE memory barrier is definitely abused in buf_pool_withdraw_blocks(): most
probably it was supposed to commit volatile variable update, which is not what
memory barriers actually do. To operate properly it needs corresponding ACQUIRE
barrier without an associated atomic operation anyway.
ACQUIRE memory barrier is definitely abused in log_write_up_to(): most probably
it was supposed to synchronize dirty read of log_sys->write_lsn. To operate
properly it needs corresponding RELEASE barrier without an associated atomic
operation anyway.
Removed a bunch of ACQUIRE memory barriers from InnoDB rwlocks. They're
meaningless without corresponding RELEASE memory barriers.
Valid usage example of memory barriers without an associated atomic operation:
http://en.cppreference.com/w/cpp/atomic/atomic_thread_fence
Replaced InnoDB atomic operations with server atomic operations.
Moved INNODB_RW_LOCKS_USE_ATOMICS - it is always defined (code won't compile
otherwise).
NOTE: InnoDB uses thread identifiers as a target for atomic operations.
Thread identifiers should be considered opaque: any attempt to use a
thread ID other than in pthreads calls is nonportable and can lead to
unspecified results.
Using numa_all_nodes_ptr was excessively optimistic. Due to
constraints in systemd, containers or otherwise mysqld could of been
limited to a smaller set of cpus. Use the numa_get_mems_allowed
library function to see what we can interleave between before doing
so. The alternative is to fail interleaving overall.
Signed-off-by: Daniel Black <daniel.black@au.ibm.com>
Contains also:
MDEV-10549 mysqld: sql/handler.cc:2692: int handler::ha_index_first(uchar*): Assertion `table_share->tmp_table != NO_TMP_TABLE || m_lock_type != 2' failed. (branch bb-10.2-jan)
Unlike MySQL, InnoDB still uses THR_LOCK in MariaDB
MDEV-10548 Some of the debug sync waits do not work with InnoDB 5.7 (branch bb-10.2-jan)
enable tests that were fixed in MDEV-10549
MDEV-10548 Some of the debug sync waits do not work with InnoDB 5.7 (branch bb-10.2-jan)
fix main.innodb_mysql_sync - re-enable online alter for partitioned innodb tables
Contains also
MDEV-10547: Test multi_update_innodb fails with InnoDB 5.7
The failure happened because 5.7 has changed the signature of
the bool handler::primary_key_is_clustered() const
virtual function ("const" was added). InnoDB was using the old
signature which caused the function not to be used.
MDEV-10550: Parallel replication lock waits/deadlock handling does not work with InnoDB 5.7
Fixed mutexing problem on lock_trx_handle_wait. Note that
rpl_parallel and rpl_optimistic_parallel tests still
fail.
MDEV-10156 : Group commit tests fail on 10.2 InnoDB (branch bb-10.2-jan)
Reason: incorrect merge
MDEV-10550: Parallel replication can't sync with master in InnoDB 5.7 (branch bb-10.2-jan)
Reason: incorrect merge
Analysis: When pages in doublewrite buffer are analyzed compressed
pages do not have correct checksum.
Fix: Decompress page before checksum is compared. If decompression
fails we still check checksum and corrupted pages are found.
If decompression succeeds, page now contains the original
checksum.
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.
we can see from the hang stacktrace, srv_monitor_thread is blocked
when getting log_sys::mutex, so that sync_arr_wake_threads_if_sema_free
cannot get a change to break the mutex deadlock.
The fix is simply removing any mutex wait in srv_monitor_thread.
Patch is reviewed by Sunny over IM.
Backport pull request #125 from grooverdan/MDEV-8923_innodb_buffer_pool_dump_pct to 10.0
WL#6504 InnoDB buffer pool dump/load enchantments
This patch consists of two parts:
1. Dump only the hottest N% of the buffer pool(s)
2. Prevent hogging the server duing BP load
From MySQL - commit b409342c43ce2edb68807100a77001367c7e6b8e
Add testcases for innodb_buffer_pool_dump_pct_basic.
Part of the code authored by Daniel Black
WL#6504 InnoDB buffer pool dump/load enchantments
This patch consists of two parts:
1. Dump only the hottest N% of the buffer pool(s)
2. Prevent hogging the server duing BP load
From MySQL - commit b409342c43ce2edb68807100a77001367c7e6b8e
Analysis: When a page is read from encrypted table and page can't be
decrypted because of bad key (or incorrect encryption algorithm or
method) page was incorrectly left on buffer pool.
Fix: Remove page from buffer pool and from pending IO.
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.
