| Commit message (Collapse) | Author | Age | Files | Lines |
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If a table has no unique indexes, write set key information will be collected on all columns in the table.
The write set key information has space only for max 3500 bytes for individual column, and if a varchar colummn of such non-primary key table is longer than
this limit, currently a crash follows.
The fix in this commit, is to truncate key values extracted from such long varhar columns to max 3500 bytes.
This may potentially lead to false positive certification failures for transactions, which operate on separate cluster nodes, and update/insert/delete table rows, which differ only in the part of such long columns after 3500 bytes border.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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Revert 88a4be75a5f3b8d59ac8f6347ff2c197813c05dc and
9d97f92febc89941784d17d59c60275e21140ce0, which had been
prematurely pushed by accident.
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This reverts commit 30dea4599e44e3008fb9bc5fe79ab5747841f21f.
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This patch is the plan D variant for fixing potetial mutex locking
order exercised by BF aborting and KILL command execution.
In this approach, KILL command is replicated as TOI operation.
This guarantees total isolation for the KILL command execution
in the first node: there is no concurrent replication applying
and no concurrent DDL executing. Therefore there is no risk of
BF aborting to happen in parallel with KILL command execution
either. Potential mutex deadlocks between the different mutex
access paths with KILL command execution and BF aborting cannot
therefore happen.
TOI replication is used, in this approach, purely as means
to provide isolated KILL command execution in the first node.
KILL command should not (and must not) be applied in secondary
nodes. In this patch, we make this sure by skipping KILL
execution in secondary nodes, in applying phase, where we
bail out if applier thread is trying to execute KILL command.
This is effective, but skipping the applying of KILL command
could happen much earlier as well.
This patch also fixes mutex locking order and unprotected
THD member accesses on bf aborting case. We try to hold
THD::LOCK_thd_data during bf aborting. Only case where it
is not possible is at wsrep_abort_transaction before
call wsrep_innobase_kill_one_trx where we take InnoDB
mutexes first and then THD::LOCK_thd_data.
This will also fix possible race condition during
close_connection and while wsrep is disconnecting
connections.
Added wsrep_bf_kill_debug test case
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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multi-byte character set
We need to set temporary buffer large enough to fit also multi-byte
characters.
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`PRIMARY` table `schema`.`child_table`
Problem was that not all normal error codes where not handled
after wsrep_row_upd_check_foreign_constraints() call. Furhermore,
debug assertion did not contain all normal error cases. Changed
ib:: calls to WSREP_ calls to use wsrep instrumentation.
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enclosed in single quotes).
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wsrep_sst_common did not correctly set name for binlog index
file if custom binlog name was used and this name was
not added to script command line.
Added test case for both log_basename and log_binlog.
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Another batch of changes that should make the SST process
more reliable in all scenarios:
1) Added hostname or CN verification when stunnel is used
with certificate chain verification (verifyChain = yes);
2) Added check for the absence of the stunnel utility for
mtr tests;
3) Deletion of working files before and after SST is done
more accurately;
4) rsync on joiner can be run even if the path to its
configuration file contains spaces;
5) More accurate directory creation (for data files and
for logs);
6) IST with mysqldump no longer turns off statement logging;
7) Reset password for mysqldump when password is empty but
username is specified;
8) More reliable quoting when generating statements in
wsrep_sst_mysqldump;
9) Added explicit generation of 2048-bit Diffie-Hellman
parameters for sockat < 1.7.3, by analogy with xtrabackup;
10) Compression parameters for qpress are read from all
suitable server groups in configuration file, as well as
from the [sst] and [xtrabackup] groups;
11) Added a test that checks compression using qpress;
12) Checking for optional utilities is modified to work even
if they implemented as built-in shell commands (unlikely
on real systems, but more reliable).
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This commit contains a large set of further bug fixes and
improvements to SST scripts for Galera, continuing the work
that was started in MDEV-24962 to make SST scripts work smoothly
in different network configurations (especially using ipv6) and
with different environment settings:
1) The ipv6 addresses were incorrectly handled in the SST script
for rsync (incorrect address substitution for establishing a
connection, incorrect address substitution for bind, and so on);
2) Checking the locality of the ip-address in SST scripts did not
support ipv6 addresses (such as "[::1]"), which were falsely
identified as non-local ip, which further did not allow running
two SSTs on different local addresses on the same machine.
On the other hand, this bug masked some other errors (related
to handling ipv6 addresses);
3) The code for checking the locality of the ip address was different
in the SST scripts for rsync and for mysqldump, with individual
flaws. This code is now made common and moved to wsrep_sst_common;
4) Waiting for the start of the transport channel (socat, nc, rsync,
stunnel) in the wait_for_listen() and check_pid_and_port() functions
did not process ipv6 addresses correctly in all cases (not for all
branches);
5) Waiting for the start of the transport channel (socat, nc, rsync,
stunnel) in the wait_for_listen() and check_pid_and_port() functions
for some code branches could give a false positive result due to
the textual match of prefixes in the port number and/or PID of
the process;
6) Waiting for the start of the transport channel (socat, nc, rsync,
stunnel) was supported through different utilities in SST scripts
for mariabackup and for rsync, and with various minor flaws in
the code. Now the code is still different in these scripts, but
it supports a common set of utilities (lsof, ss, sockstat) and
is synchronized across patterns that used to check the output
of these utilities;
7) In SST via mariabackup, the signal about readiness to receive data
is sometimes sent too early - immediately after listen(), and not
after accept() (which are called by socat or netcat utility).
8) Checking availability of the some options of some utilities was
done using the grep pattern, which easily gives false positives;
9) Common name (CN) for local addresses, if not explicitly specified,
is now always replaced to "localhost" to avoid the need to generate
many separate certificates for local addresses of one machine and
not to depend on which the local address is currently used in test
(ipv4 or ipv6, etc.);
10) In tests galera_sst_mariabackup_encrypt_with_key_server and
galera_sst_rsync_encrypt_with_key_server the correct certificate
is selected to avoid commonname (CN) mismatch problems;
11) Further refactoring to protect against spaces in file names.
12) Further general refactoring to eliminate bash-specific constructs
or to improve code readability;
13) The code for setting options for the nc (netcat) utility was
different in different scripts for SST - now it is made identical.
14) Fixed long-time broken encryption via xbcrypt in combination with
mariabackup and added support for key-based encryption via openssl
utility, which is now enabled by default for encrypt=1 mode (this
default mode can be changed using a new configuration file option
"encypt-format=openssl|xbcrypt", which can be placed in the [mysqld],
[sst] or in the [xtrabackup] section) - this change will allow us
to use and to test the encypt=1 encryption without installing
non-standard third-party utilities.
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SSL practices
and configuration.
1. Pass joiner's authentication information to donor together with address
in State Transfer Request. This allows joiner to authenticate donor on
connection. Previously joiner would accept data from anywhere.
2. Deprecate custom SSL configuration variables tca, tcert and tkey in favor
of more familiar ssl-ca, ssl-cert and ssl-key. For backward compatibility
tca, tcert and tkey are still supported.
3. Allow falling back to server-wide SSL configuration in [mysqld] if no SSL
configuration is found in [sst] section of the config file.
4. Introduce ssl-mode variable in [sst] section that takes standard values
and has following effects:
- old-style SSL configuration present in [sst]: no effect
otherwise:
- ssl-mode=DISABLED or absent: retains old, backward compatible behavior
and ignores any other SSL configuration
- ssl-mode=VERIFY*: verify joiner's certificate and CN on donor,
verify donor's secret on joiner
(passed to donor via State Transfer Request)
BACKWARD INCOMPATIBLE BEHAVIOR
- anything else enables new SSL configuration convetions but does not
require verification
ssl-mode should be set to VERIFY only in a fully upgraded cluster.
Examples:
[mysqld]
ssl-cert=/path/to/cert
ssl-key=/path/to/key
ssl-ca=/path/to/ca
[sst]
-- server-wide SSL configuration is ignored, SST does not use SSL
[mysqld]
ssl-cert=/path/to/cert
ssl-key=/path/to/key
ssl-ca=/path/to/ca
[sst]
ssl-mode=REQUIRED
-- use server-wide SSL configuration for SST but don't attempt to
verify the peer identity
[sst]
ssl-cert=/path/to/cert
ssl-key=/path/to/key
ssl-ca=/path/to/ca
ssl-mode=VERIFY_CA
-- use SST-specific SSL configuration for SST and require verification
on both sides
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>
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1. Fix eval command line to correctly pass stunnel option to rsync on donor.
2. Deprecate `tkey`, `tcert` and `tca` options in [sst] section in favor of
conventional `ssl-key`, `ssl-cert` and `ssl-ca`, but keep their precedence
for backward compatibility.
3. Default to require SSL encryption if at least SSL key and cert files are
specified in configuration, either in [sst] or [mysqld] sections.
4. Enable `verify*` option for stunnel on donor only if
a. CA file is specified somewhere in the configuration
b. it is explicitly requested in [sst] section by either specifying
ssl-mode or CA file there. In this case if ssl-mode is not explicitly
given, it defaults to VERIFY_CA.
ssl-mode maps to stunnel options as follows:
VERIFY_CA -> verifyChain = yes
VERIFY_IDENTITY -> verifyPeer = yes
Example to require donor to verify joiner identity:
```
[mysqld]
ssl-cert=/path/to/cert
ssl-key=/path/to/key
ssl-ca=/path/to/ca
[sst]
ssl-mode=VERIFY_IDENTITY
```
5. If SSL verification is requested, joiner verifies donor by checking the
secret passed to donor via SST request.
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>
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After switching to the new mariabackup interface (instead of
the outdated innobackupex interface, which is supported for
compatibility), we need to explicitly pass a path to the datadir
directory as a parameter, since in the new interface the value
of this option is not automatically set in such a way that it
always matches the SST/IST logic. This commit adds passing this
option as an explicit parameter to mariabackup. This commit also
removed unnecessary options that are not used and not supported
by mariabackup.
Also, numerous flaws in the common wsrep_sst_common script have
been fixed:
1) There are many bash-specific constructs in the script that
may not be supported by other interpreters, which can lead
to the most unexpected errors during SST, because failures
in the interpretation of bash-specific constructs lead to
incorrect parsing of arguments;
2) There is parse_cnf() function which is often called by other
scripts for the "mysqld" or "--mysqld" group, but it does not
take into account the default group suffix, which leads to
reading values only from the default group, which then leads
to errors due to reading the default values instead of the
values for a specific group;
3) Some options such as --user, --innodb-data-home-dir or --datadir
are not removed from the --mysqld-args list, although they are
processed inside scripts (and passing of these options funther
may cause problems for mariabackup);
4) If an argument that the script understands is present in
the --mysqld-args list twice, then this causes SST to fail,
instead of reading the most recent value;
5) The "--host" parameter is technically still supported among
the arguments of the SST scripts, but in reality scripts do not
work with it as expected, especially if it has an IPv6 address;
6) If the port number is absent in the --address parameter value,
but the port number is explicitly passed through the --port
argument, then the scripts for mariabackup and xtrabackup-v2
fail;
7) If a new address interface is used (with the --address parameter),
then automatic default port substitution is not performed, although
it is supported for the legacy --host/--port interface.
8) If there are spaces in the parameter values after --mysqld_args,
then their further transfer does not occur correctly, which
causes mariabackup to fail during SST - the space splits
the argument in such a way that it breaks the parsing of the
following parameters;
9) If most of the parameters that are names or paths to the files
or directories contain spaces, then SST scripts fail in an
unpredictable way due to incorrect variable substitutions;
10) If the --log-bin option is passed among the arguments of myqlds
(--mysqld-args) without a parameter, and the --binlog option
is not specified, then the script cannot substitute the default
name for binlog and cannot construct binlog name using the
--log-basename argument (which is against server specifications);
11) Tail slashes are not removed from the directory names, which,
upon further substitution, leads to the appearance of a double
slash in the file paths;
12) The explicit --binlog parameter (which is now always transmitted
from the server side) and the "hidden" --log-bin parameter in the
list of arguments after --mysqld-args are perceived as two different
parameters in different parts of the scripts, and if they are do not
match for some reason, this will lead to failures during SST;
Also, all new changes from the 10.6 branch have been migrated here,
including the latest pull requests for authentication (only the part
that concerns SST scripts).
It also fixes dozens of other bugs in all SST scripts.
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telling, never turns it off
Removed explicit InnoDB monitor startup and used just functions
to print current lock information.
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Problem was that we should skip strict password validation on
applier nodes similarly as is done for slave nodes.
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Replace unnecessary sleeps with real wait_conditions to make
sure correct cluster sizes.
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The auto-increment variables may change intermittently during
the execution of some tests from the Galera mtr suite, causing
these tests to fail. This patch creates conditions in which
unpredictable changes to these variables are not possible
during the execution of those tests in which this problem
is noticed or their values are restored before the end of
testing.
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Virtual column fields are not found in prebuilt data type, so we should
match InnoDB fields with `get_innobase_type_from_mysql_type` method.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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* Remove usage of wsrep_provider variable in galera_ist_restart_joiner
* Rename galera_load_provider.inc and galera_unload_provider.inc to
galera_stop_replication.inc and galera_start_replication.inc. Their
original names were no longer reflecting what these include files do.
followup for ce3a2a688db
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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Mariabackup SST fails if "--log-bin" option is added with no value
to command line parameters at server startup. This is because the SST
scripts do not correctly interpret the "--- log-bin" option without a
value. This patch adds correct handling of the "--log-bin" parameter
without value to the general part of the parameter parsing (for SST
scripts) and fixes the problem. Also added a test that checks the
correct operation of the server after the fix.
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TTASEventMutex<GenericPolicy>]: Assertion `!is_owned()' failed. assertion
MDEV-24649 galera.galera_bf_lock_wait MTR failed with sigabrt: Assertion `!is_ow
ned()' failed in sync0policy.ic on MutexDebug with Mutex = TTASEventMutex<GenericPolicy>
Bug was fixed as part of MDEV-23328, this just adds test cases to
regression set.
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Keyvalue can be longer than REC_VERSION_56_MAX_INDEX_COL_LEN
and this leads out-of-array reference. Use dynamic memory
allocation using actual max length of key value.
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this should simplify run-time cluster management
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The test requires adaptation for MariaDB, which is done
in this patch. In addition, this patch includes a fix for
the SST script startup code that adds escaping for special
characters on the command line (in case they are contained
in the arguments to mysqld). The fix does not require
separate tests, as the required tests are already part
of the mtr suite for Galera.
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It seems that memory is not freed when updated value is NULL or
when wsrep is not initialized before shutdown.
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Some DML operations on tables having unique secondary keys cause scanning
in the secondary index, for instance to find potential unique key violations
in the seconday index. This scanning may involve GAP locking in the index.
As this locking happens also when applying replication events in high priority
applier threads, there is a probabality for lock conflicts between two wsrep
high priority threads.
This PR avoids lock conflicts of high priority wsrep threads, which do
secondary index scanning e.g. for duplicate key detection.
The actual fix is the patch in sql_class.cc:thd_need_ordering_with(), where
we allow relaxed GAP locking protocol between wsrep high priority threads.
wsrep high priority threads (replication appliers, replayers and TOI processors)
are ordered by the replication provider, and they will not need serializability
support gained by secondary index GAP locks.
PR contains also a mtr test, which exercises a scenario where two replication
applier threads have a false positive conflict in GAP of unique secondary index.
The conflicting local committing transaction has to replay, and the test verifies
also that the replaying phase will not conflict with the latter repllication applier.
Commit also contains new test scenario for galera.galera_UK_conflict.test,
where replayer starts applying after a slave applier thread, with later seqno,
has advanced to commit phase. The applier and replayer have false positive GAP
lock conflict on secondary unique index, and replayer should ignore this.
This test scenario caused crash with earlier version in this PR, and to fix this,
the secondary index uniquenes checking has been relaxed even further.
Now innodb trx_t structure has new member: bool wsrep_UK_scan, which is set to
true, when high priority thread is performing unique secondary index scanning.
The member trx_t::wsrep_UK_scan is defined inside WITH_WSREP directive, to make
it possible to prepare a MariaDB build where this additional trx_t member is
not present and is not used in the code base. trx->wsrep_UK_scan is set to true
only for the duration of function call for: lock_rec_lock() trx->wsrep_UK_scan
is used only in lock_rec_has_to_wait() function to relax the need to wait if
wsrep_UK_scan is set and conflicting transaction is also high priority.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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failed: 1205: Lock wait timeout exceeded
Add wait_conditions to verify correct database state before
next operation.
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Use debug_sync to force FTWRL to pause in correct state.
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At end_connection make sure we have wsrep before trying to free
connection assigned to it.
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If log_slave_updates==OFF, wsrep applier threads used to be configured
with option: thd->variables.option_bits&= ~(OPTION_BIN_LOG);
(i.e. like sql_log_bin=ON). And this was regardless of log-bin configuration.
With this, having configuration of: --log-bin && --log-slave-updates=OFF,
local threads used binlogging, but applier threads did not. And further:
local threads went through binlog group commit, while applier threads did
direct commits. This resulted in situation, where applier threads entered
earlier in wsrep XID checkpointing, and could sync their wsrep XID out of order.
Later local thread commit would see that higher seqno was already checkpointed,
and fire an assert because of this.
As a fix, applier threads are now forced to enable binlogging regardless of
log-slave-updates configuration.
This PR comes with new mtr test: galera.MDEV-24327, which causes a scenario
where applier transaction is applied and committed while earlier local transaction
is parked before commit order monitor enter. A buggy mariadb versoin would fail
for assertion because of wsrep XID checkpoint order violation.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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Add test case
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Add primary key and wait condition.
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Changed the test so that it does not rely on specific auto increment
ids. With Galera's default wsrep_auto_increment_control setting it is
not guaranteed that auto increments always start from 1. The test was
occasionally failing due to result content mismatch.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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Deadlock is possible between applier thread and local committing thread with active FLUSH TABLE.
Applier thread should skip table share checks and locks when opening table.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
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To fix this, it is necessary to add an option to exclude the
database with the name "lost+found" from processing (the database
name will be checked by the check_if_skip_database_by_path() or
by the check_if_skip_database() function, and as a result
"lost+found" will be skipped).
In addition, it is necessary to slightly modify the verification
logic in the check_if_skip_database() function.
Also added a new test galera_sst_mariabackup_lost_found.test
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Add necessary wait_conditions to stabilize test.
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galera_gcache_recover_full_gcache.test: assert_grep.inc failed
Grep only the fact that we need to fall back to SST.
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not transition to state READY
Replace sleeps with proper wait_conditions to wait correct
cluster configuration.
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Remove infinite procedure and use direct INSERTs.
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While doing TOI buffer OR REPLACE option was not added to replicated
string.
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This commit contains a fix and extended test case for a ASAN failure
reported during galera.fk mtr testing.
The reported heap buffer overflow happens in test case where a cascading
foreign key constraint is defined for a column of varchar type, and
galera.fk.test has such vulnerable test scenario.
Troubleshoting revealed that erlier fix for MDEV-19660 has made a fix
for cascading delete handling to append wsrep keys from pcur->old_rec,
in row_ins_foreign_check_on_constraint(). And, the ASAN failuer comes from
later scanning of this old_rec reference.
The fix in this commit, moves the call for wsrep_append_foreign_key() to happen
somewhat earlier, and inside ongoing mtr, and using clust_rec which is set
earlier in the same mtr for both update and delete cascade operations.
for wsrep key populating, it does not matter when the keys are populated,
all keys just have to be appended before wsrep transaction replicates.
Note that I also tried similar fix for earlier wsrep key append, but using
the old implementation with pcur->old_rec (instead of clust_rec), and same
ASAN failure was reported. So it appears that pcur->old_rec is not properly
set, to be used for wsrep key appending.
galera.galera_fk_cascade_delete test has been extended by two new test scenarios:
* FK cascade on varchar column.
This test case reproduces same scenario as galera.fk, and this test scenario
will also trigger ASAN failure with non fixed MariaDB versions.
* multi-master conflict with FK cascading.
this scenario causes a conflict between a replicated FK cascading transaction
and local transaction trying to modify the cascaded child table row.
Local transaction should be aborted and get deadlock error.
This test scenario is passing both with old MariaDB version and with this
commit as well.
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During SST we need to let FTWRL to use normal timeout method
even when client is disconnected.
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hang.
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Fixed by new recording test recording
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The sporadic test hangs happen because of mutex dealock between innodb
background threads and two test connection executions.
The test sets variable innodb_disallow_writes, which blocks all writes
to filesyste. The test logic is to execute an INSERT, which should hang
because of filesytstem writes are blocked, and through another session
verify by SELECT that this hanging happens. The SELECT session will then
release innodb_disallow_writes blocking.
However, filesystem write blocking affects also innodb background threads
and they may hang while keeping some other resources locked.
As an example, in one test hang situation, buffer pool access was blocked.
And, if buffer pool is blocked, the test connections will be blocked as well,
and the SELECT session will not be able to continue to release the
innodb_disallow_writes.
The fix in this commit is refactoring of the test logic.
The test will now set first innodb_disallow_writes blocking, and then record
a hash of data directory's filesystem contents. This works as checksum of the
state of data on the datadirectory.
Then some SQL load is tried on both nodes, these sessions will be blocking
due to frozen file system state. The test will have a short sleep to allow
innodb background threads to loop and possibly encounter innodb_disallow_writes
blocking as well.
After the sleep, the test will record file system checksun for the second time,
and then release the innodb_disallow-writes blocking.
Finally, the two checksums are compared, they should be identical to verify that
nothing was written on datadirectory during the test execution.
The checksum is implemented by md5sum hash over all files found in datadirectory
by find command. all these file hashes are hashed together by one more md5sum.
The test therefore depends on md5sum and find. find may work differently with some
OS distributions, e.g. freebsd may be problematic.
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