MDEV-31088 Server freeze due to innodb_change_buffering
A 3-thread deadlock has been frequently observed when using
innodb_change_buffering!=none and innodb_file_per_table=0:
(1) ibuf_merge_or_delete_for_page() holding an exclusive latch on the block
and waiting for an exclusive tablespace latch in fseg_page_is_allocated()
(2) btr_free_but_not_root() in fseg_free_step() waiting for an
exclusive tablespace latch
(3) fsp_alloc_free_page() holding the exclusive tablespace latch and waiting
for a latch on the block, which it is reallocating for something else
While this was reproduced using innodb_file_per_table=0, this hang should
be theoretically possible in .ibd files as well, when the recovery or
cleanup of a failed DROP INDEX or ADD INDEX is executing concurrently
with something that involves page allocation.
ibuf_merge_or_delete_for_page(): Avoid invoking fseg_page_is_allocated()
when block==nullptr. The call was redundant in this case, and it could
cause deadlocks due to latching order violation.
ibuf_read_merge_pages(): Acquire an exclusive tablespace latch
before invoking buf_page_get_gen(), which may cause
fseg_page_is_allocated() to be invoked in ibuf_merge_or_delete_for_page().
Note: This will not fix all latching order violations in this area!
Deadlocks involving ibuf_merge_or_delete_for_page(block!=nullptr) are
still possible if the caller is not acquiring an exclusive tablespace latch
upfront. This would be the case in any read operation that involves a
change buffer merge, such as SELECT, CHECK TABLE, or any DML operation that
cannot be buffered in the change buffer.
MDEV-31373 innodb_undo_log_truncate=ON recovery results in a corrupted undo log
recv_sys_t::apply(): When applying an undo log truncation operation,
invoke os_file_truncate() on space->recv_size, which must not be
less than the original truncated file size.
Alternatively, as pointed out by Thirunarayanan Balathandayuthapani,
we could assign space->size = t.pages, so that
fil_system_t::extend_to_recv_size() would extend the file back
to space->recv_size.
MDEV-31347 fil_ibd_create() may hijack the file handle of an old file
fil_space_t::add(): If a file handle was passed, invoke
fil_node_t::find_metadata() before releasing fil_system.mutex.
The call was moved from fil_ibd_create().
This is a 10.5 version of commit e3b06156c6ecd5d3fd4376ee025df1ab45311a6d
from 10.6.
MDEV-31347 fil_ibd_create() may hijack the file handle of an old file
fil_ibd_create(): Hold fil_system.mutex until fil_node_t::find_metadata()
has completed, so that node->handle cannot be closed by a concurrent
thread. This race condition was introduced
in commit 10dd290b4b8b8b235c8cf42e100f0a4415629e79 (MDEV-17380).
MDEV-31353 InnoDB recovery hangs after reporting corruption
recv_recover_page(): Remove some code which was added in
commit 0b47c126e31cddda1e94588799599e138400bcf8 with
no good reason and which would cause a hang after a corrupted
page was reported during crash recovery.
Tested by: Matthias Leich
30fb72c...
by
Tuukka Pasanen <email address hidden>
MDEV-31331: Fix cut'n'paste variable name in Debian pre-inst script
There is unwanted cut'n'paste variable name in Debian pre-inst
script which causes:
df: '': No such file or directory
/var/lib/dpkg/tmp.ci/preinst: line 215: [: : integer expression expected
Rename variable to correct one and make check that that directory
or symlink really exists. If it does not then fail with error
and message.